This idea may work in a place where everyone knows your name. However when faced with people that they will never see again, give me a break.
I would like to see this tried in a biker bar. Really, if the owners are bikers then it just may well work.
Bikers will for the most part look out for their friends Strangers come in drink and eat and refuse to donate what they have or wash dishes, ----someone call 911.