I'm always wondering what waitresses think about the new way of tipping in restaurants.
It used to be you just put your few dollars on the table and they could always see immediately if you were a nice guy or a bum. Now they have the extra intermediary step, in some cases, of taking your debit card, running it, bringing you back a bunch of receipts, and hoping that you'll know enough to fill it in properly.
(By the way, using a debit card takes away all your anonymity, since your name's printed right on the thing. It's disconcerting to hear the waitress call you by name.)
In some cases, then, the waitress returns to your table after you're gone, gets the black receipt book, and presumably looks to see if you're a prince or a bum. So it's not that much different. But there's other places where you go to the cash register, leaving nothing behind on the table, and what they wind up with is a stack of tickets at the register.
Unless they're very forward to be at the register going through the tickets, it's more or less a mystery to them till some hours later whether you were a hero or goat. By then you're long gone and they can't run out to your car and let the air out of the tires or put sugar cubes in your gas.
From the customer's point of view, it feels kind of funny not leaving a few bucks on the table. Except it always bothered me to do so, since you never know whether the people at the other tables were thieves. Still, you want the waitress to know you were decent enough and not a freeloader, if that makes any difference.
There was a guy on the news the other day who advocated not tipping at all unless it would have something to do with getting better service or some other advantage next time. That's definitely the pragmatic/selfish approach. The way I'd see it is there might not be a next time. The waitress would see you coming and put you right next to the aquarium right when it was time for it to be cleaned.
At some time you'd have to prime the pump, meaning be preemptive in giving a tip. Then it would have to be memorable enough that she'd remember it next time. Two or three dollars wouldn't be enough to stand out in her memory. You'd have to give fifty bucks for her to remember it. And say she did remember it, you've got the problem of having to match or exceed it next time. Bottom line, I'd forget the pragmatic/selfish approach and just help her along with making a decent wage.