Mystery diners note this...
... because if their waiters ask people if there's anything wrong with their meal and they say no (or the reverse and they say yes) then they're less likely to make shit up later to try to claim a free meal. The waiters aren't asking for your benefit, or because it will make you feel nice.

It's the same reason coffee cups say "Warning: contents may be hot". It's not a service, it's a safeguard.
(sabre-tooth monkey, Fri 28 May 2010, 16:24, 2 replies)

Is that what it's really about?
In that case I hate restaurant owners even more.
( Olembe Refuses to write in this space, Fri 28 May 2010, 16:41, closed)

It doesn't work then.
I've seen a few occasions where the quality of the meal was remarked upon after this point but a discount was given.
Most recently at Frankie & Bennies in Manchester when my girlfriend's steak was overcooked but she hadn't tried enough to mention it then and, besides, didn't fancy a spit-marinade.
Besides, since you're paying for the goods and service after the fact you are under no legal obligation to pay the price the restaurant ask -- you could even leave your details and go without paying.
(Me, I'm not... in any way intoxicated, Fri 28 May 2010, 17:35, closed)