[Bud]

The onus could just as fairly be applied to Groupon itself as to its customers; shouldn't Groupon be helping the restaurants it does business with, by encouraging/reminding customers to tip servers fairly, and not harm the staff of its business partners?

[3am]

They encourage that prominently in several places, including this message on the actually coupon voucher:

"*Remember: Groupon customers tip on the full amount of the pre-discounted bill (and tip generously). That's why we are the coolest customers out there."

I've got no lost love for GroupOn, but this massive pile on/proof by anecdote thing is not a dignified moment for HN.