Some people are more inclined to give when they know their friends will find out.
Ingvar Kamprad's Ikea revolutionised retail by popularising flat-pack furniture and building maze-like stores.
Marketing has moved from a focus on the product itself to the consumer, who they are and finally, how they think.
Will you buy the new iPhone straight away?
Or do you buy your smartphone based on its cost-benefits? Either way Apple might be using your own psychology against you.