Self herding

How many times did you end up buying a bigger or newer costlier coffee at your favorite roaster?

You will know only if you check your expenditure on coffee.

You repeated your own behavior and ended up drinking costlier coffee in bigger mugs.

But what about the sample coffee barista offered you?

Well congratulations, you fell for self-herding. It is a common sales trick applied by coffee/candy/ice cream shops.