I’ve seen this in some upscale places I’ve eaten in, but not in mid to mass class establishments.

Which begs the question why they don’t do this considering that this directly affects employees pay?

Either they don’t know, or they don’t care, Here’s to hoping they do not know and would gladly implement the extra management overhead that such a scheme would entail if given the chance.

To illustrate why it’s popular, I’ll use an analogy from the restaurant industry. Have you ever noticed that at restaurants, your waiter doesn’t bring your food? Other waiters always bring out your food, during which time your waiter is nowhere to be seen. This is so that if you become infuriated because you specifically ordered tartar sauce on the side, and after a 45-minute wait the chef seems to have emptied the entire bottle of tartar sauce on your fish sandwich in some sort of twisted artistico-culinary attempt to make it look like he threw up on it, then you don’t blame your waiter. Instead, you unwittingly direct your anger at the person who brought your food, who makes sympathetic noises (“Gosh, I’m so sorry – I can’t believe they messed that up!”) and runs away, never to be seen again. After it’s eventually resolved (by still other people bringing replacements out), your waiter finally rematerializes and apologizes for the kitchen screwup.

Stevey’s Blog Rants: The Bellic School of Management Training.