[newsclues]

People will give up passwords for a cheap pen. Free stuff is a hack for many peoples minds.

There is a reason salespeople will bring you a coffee and donut.

[petercooper]

Bit of a tangent, but there are further psychological reasons why hot drinks are used in sales situations: https://news.yale.edu/2008/10/23/hot-coffee-we-see-warm-hear...