Remember with most customers paying for cards tips have a paper trail which the owner has to process. If that paper trail Bob regularly gets crappy tips while Frank working right next to him get great tips might be time for a chat with Bob.
Not necessarily.
Some people (ahem, men) tip on the credit card slip at a standard rate that their wives (or boss if they are on an expense account) will approve of and leave a cash tip separately.
I think that’s an excellent counterpoint. I do think, however, that I’d be a lot more inclined to do something about Bob much quicker if I’m directly paying him $10 hr/ 20% of sales than I would be if I’m only directly on the line for a couple bucks an hour. True, he’s hurting business both ways, and under either system he’ll probably get the axe sooner or later if he doesn’t shape up, but Bob is far more directly accountable to me if I’m the only one paying him for what he does.