Walk into McDonald's and the self-service kiosks look like a simple upgrade. Faster ordering, fewer queues, more convenience. But from a behavioural psychology and business perspective, they serve a much more strategic purpose. They are designed to influence how customers make decisions and ultimately increase how much they spend.

There’s nothing quite like crouching down in a supermarket aisle to take a photo of yourself holding a meal deal all in the name of having something to discuss in the classroom. It might sound a bit daft. But stick with me. When I buy a meal deal, I don’t choose what I actually fancy eating. I choose what gives me the most value. I mainly drink water. Yet if there’s a drink in the fridge that costs £2.50 on its own, that’s the one going into my meal deal. Add a £3.40 wrap and