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Science-based tricks restaurants use to make you spend

You might like to think you have a good eye for a deal and don’t get fooled by so-called special offers or overpriced dishes when you go to eat out.

But restaurants employ such a wide variety of subtle psychological tricks to encourage customers to part with their money, that even the most canny diner would be hard pressed to spot them all. 

The tricks of the trade have been revealed by the US YouTube channel SciShow Psych, which says you’re so hard-wired to fall for them that you may well keep doing so even after they’ve been brought to your attention.

They include serving food on a particular size of plate to encourage you to either order more or take less from the buffet, and using heavier cutlery to make you believe you’re eating a better quality meal. 

It also revealed why we drink beer faster from a curved glass than a straight one – making our trips to the bar that much more frequent.  

Tricks of the restaurant trade have been revealed by SciShow Psych, including fooling people into paying more with attractive presentation (stock image)


According to this principle, two identical circles can look completely different if circles of different sizes are drawn around them. 

If the inner circle is surrounded by a large one, it will appear smaller. However, if it’s surrounded by a small circle it will appear bigger. 

This comes in handy for restaurateurs when it comes to deciding on the size of plate to use. 

People tend to overestimate the portions they want if they have a big plate, which is why establishments such as all-you-can-eat buffets provide smaller dishes so that customers don’t help themselves to too much food, eating into their profits.  

Meanwhile, restaurants where you’re ordering off a menu tend to serve the main course on a larger plate. 

This tricks you into thinking you’ve not eaten so much and you have room for dessert. 


Cultural influences dictate that certain beverages belong in particular vessels, such as champagne in a flute and red wine in a larger, wider glass than white. 

But if your drink turns up in a different glass to what you’re expecting the cognitive dissonance actually causes mental distress.   

It makes the experience less pleasant and you don’t want to pay as much for it.  


Pound signs are a disappearing feature from menus these days, with many restaurants opting to simply put a number beside the dish. 


1. Numbers instead of pound signs.

2. Small plates at buffets to stop you eating more.

3. Big plates in restaurants to make you think you’ve eaten less and order dessert.

4. Curved glasses to make you drink more.

5. The ‘appropriate’ glass to make you feel comfortable.

6. Quality cutlery and crockery that makes you value food more. 

7. Bigging up the food with descriptive adjectives. 

8. Tall glasses to create the illusion you’re getting more alcohol. 

9. Serving desserts in circular portions to make them seem sweeter. 

10. Artistic presentation to persuade you to part with your money.  

For example, writing 10, rather than £9.99, encourages people to spend more because the lack of pound signs helps them to stop thinking about the money they’re going to spend.


People tend to drink beer faster from curved glasses over straight ones. 

That’s because our brains tend to judge how much liquid is left based on how far up the glass it is. 

But if you look at the halfway point on a curved glass, it’s not the true halfway mark because the upper half holds more liquid.  

When you think you’ve only finished half your beer, you’re actually more than 50 per cent of the way through. And of course the faster you drink the quicker you need to buy a refill. 


A bar can trick you into thinking you’re getting more for your money by serving your beverage in a tall, skinny glass as opposed to a short, wide one. 

The horizontal vertical illusion makes us think that vertical lines seem longer than horizontal ones of the same length, probably because our visual field is wider than tall.

So if you’re looking at the drinks menu you’ll probably think it’s worth paying for that £12 cocktail in a taller glass – because you believe you’re getting a bigger drink. 


Shape symbolism can influence the way we perceive things to taste as we associate roundness with sweetness and angles with bitterness. 

People will think a round chocolate is sweeter than squares from the exact same bar and beer from a curved glass is fruitier. 

So a restaurant can make that cheesecake taste much more palatable to you, simply by giving you a round serving rather than a square slice.  

The shape of your glass has a bearing on the value you place on your drink, how quickly you consume it and whether you feel comfortable paying for it (stock image) 

The shape of your glass has a bearing on the value you place on your drink, how quickly you consume it and whether you feel comfortable paying for it (stock image) 


This principle makes us transfer the properties of the plate we eat from or the utensils we use on to the food.  

For instance, the weight of heavy cutlery will make you associate it with quality – which is why people have reported that yoghurt tastes better with a silver spoon rather than a plastic one.  

When you’re dining out, notice the quality of the cutlery and whether something is served on an attractive plate – and then question whether you’re more impressed by these trimmings than the actual food. 

The buzzwords that may not mean what you think

An investigation for a recent episode of Channel 4’s Tricks of the Restaurant Trade revealed that many chains use buzzwords such as ‘hand-made’, ‘home-cooked’, or ‘fresh’, even though the food hasn’t been prepared in the way it is being described.

‘Home-cooked’ – Dr Richard Hyde, a law professor at the University of Nottingham, said that restaurants can call something ‘home-cooked’ even if it hasn’t been cooked in a home environment. The food can be cooked in an industrial or professional kitchen and still be called home-cooked, if it has been cooked in a way someone could feasibly do at home.

‘Hand-made’ – Remarkably, something doesn’t actually need to be made by hand and it could still be called ‘hand-made’, according to Dr Hyde. Even if large machines such as blenders are used, it can be called hand-made if the devices are big versions of ones you could get for a domestic kitchen. The food can’t be made on an industrial scale – but it could still be made in a factory.

‘Fresh’ –  Dr Hyde says an item doesn’t need to be made fresh on the premises for it to be called ‘fresh’ – it just can’t contain any artificial preservatives. Also, as long as some parts of a product are made fresh, it can be described in that way, even if part of it has been previously frozen.


It seems like an obvious one, but plating matter. 

People who were presented with the exact same salad ingredients tossed, lined up on the plate or artistically arranged said they knew the would like the latter best before they had even tasted it.  

After they’d eaten, they rated it 29 per cent than the other two identical salads. 

We all know that nicer presentation is a no-brainer when it comes to convincing people to part with money, but next time you’re eating out question whether you’re paying for style over substance. 


Again, it will come as no shock that restaurants will use evocative descriptions on the menu to tempt diners as opposed to relying on the basics. 

Who wouldn’t rather have ‘succulent 28 day aged sirloin with handcut fries’ over ‘steak and chips’? 

However it again pays to question whether the price of the meal really seems worth it for what you’re getting or whether you’re being lured in by the fancy description.