Tipping. Tipping shifts the cost an labor of the business onto the customer.

- Restaurant owners don't pay their employees enough, so customers have to make up the difference. Nice customers pay more. Assholes get a discount.

- Tipping creates unnecessary competition between employees, making some shifts/sections more valuable. Again, rewarding the assholes who only take the good shifts.

- "But it rewards/punishes your waiter!" Oh, so not only am I paying for assholes meals, but I'm now doing the manager's job for them? I'm a programmer, and when a user catches a bug, that's considered a massive failure on the part of dev, management, and QA.

And before anyone accuses me of just being stingy, I consistently tip >20%. It's a systemic problem and I'm not going to make it worse by punishing it's victims.