Imagine: you go to the store to buy milk, and the milkman explains to you that you can have chocolate milk for a few cents instead of simple. And you loveeee milk, so the chocolate would be nice to have. The milkman has persuaded you to get something additional and more expensive - that's upselling. He is a sneaky man, but you get happier and don't mind it 😉

Confront with cross-selling.