PDT 2/2 : Why has tipping increased?

[Riverman]

I am 24 with a ton of friends making $150k+. Two points:

1. The phenomenon is 100% confined to cities where young people make a ton of money

2. The rise in tipping is due to young people (under 40) for two reasons:

a) They have never experienced a real recession
b) They are (finally) being paid their market worth.