Some restaurants make a virtue out of turning their kitchens as a kind of attractive sideshow for their diners; most restaurants though, do all their cooking behind those huge swing doors (the kind that have been the inspiration for all kinds of comedic movie situations with people mistaking the entry side of those swing doors for the exit side). You never know what really goes on behind those doors (except for when you see some of those sensational hidden camera videos on TV about restaurant employees not washing their hands after a visit to the restroom, and so on). But there is a lot more than mere unplanned-for uncleanliness that goes on behind those kitchen doors in any restaurant. Even some of the ritziest places can do some pretty unglamorous stuff to save some money.
Okay let's start with and the ultimate in cutting corners when it comes restaurant food - serving meat that's clearly gone bad. To lots of classy steakhouses, the feeling of throwing away a few steaks everyday because the meat's gone bad, can be a very painful experience. Steaks cost money, you know. And so, they keep them, and keep them, and keep them. When some unlucky customer happens to like his meat well done when he orders a steak, that's the chance that the restaurant looks for. Well-cooked stuff can hide a multitude of sins. A good idea when eating out would be to never order anything that's more cooked than medium rare.
How about the thought that when you order restaurant food, you get something completely different that's disguised cleverly to look like what you ordered? For instance, when you order coffee or tea, is that little jug of cream that comes alongside it, really cream? At all kinds of upscale restaurants, only a thin top layer is really cream. The rest of it is cheaper powdered creamer. Decaffeinated coffee is more expensive. Since the only perceptible difference between decaf and regular is that decaf tastes poorer, restaurants find it especially easy to pass regular off as decaf. It's cheaper, and it makes for better customer satisfaction. The episode in Seinfeld where they have a fat-free yogurt shop passing off regular full fat yogurt as fat-free wasn't really an exaggeration. They do this kind of thing with every kind restaurant food everywhere they can get away with it.
Perhaps one of the worst scams that restaurant bars try to get away with has to do with what you get at their bars. The first time a customer orders a drink like scotch or vodka, they give him the real stuff. Once he is a little high though and orders a second or third drink, they substitute a cheap and poor quality instead; they hope that in his drunkenness, the customer will not notice. They do the same thing for people who try to order beer. After the first pitcher, every subsequent order arrives half adulterated with seltzer.