With respect to Bitter Waitress's site, I wonder how many reports of the large-party "shitty tips" fail to take into account the fact that many restaurants automatically add a 15-20% gratuity on to the bill for parties, say, over 8 or more. I certainly hope these folks don't expect an additional 15-20% on top of THAT...
From the numbers I saw all those things were spelled out. That said, mandated gratuities have generally rubbed me the wrong way, particularly since the number in one's party has seemed to drop over the years.
Well, I saw one comment, though, that claimed that the waiter only received a 14 % tip, but in the comments it said something like, "good thing there's a minimum 18% for large parties." Sounds like maybe that tipper left 14% of the total that already included and 18% tip.
Restaurants always say you can raise or lower the so-called mandatory tip as you like. That having been said, I question whether some of those large parties reported on the STD actually (a) did not have a mandatory tip imposed, and (b) if they did, that they lowered it to whatever low level was being claimed on the site.
Well, it is possible this could have been the case in some circumstances. On the other hand, there were an awful lot of parties for two or four.