I understand what you’re saying, and what you’re saying is only concerned with individuals, not systems.
What I’m saying is that regardless of how many individual people turn that job down, the job listing at that wage will still exist. Eventually, someone who is down on their luck will become desperate enough to take it because they don’t have any other options left.
They could be homeless people trying to afford the deposit on an apartment, or single dads trying to pay for field trips for their kids, or ex-cons locked out of conventional employment trying desperately to earn an honest living, or college students trying to buy one used textbook, or even uneducated twenty-somethings trying to build work history so they can stop working for tips.
All of those desperate people, the people who have no choice but to tolerate the wage that you have too much self-respect to accept–they deserve nice things too. Their boss is a greedy, insufferable bastard who is willing to pay them the minimum that he is legally required to. If he could pay his employees less, he would do it in a heartbeat. By refusing to tip, you are climbing in to the same boat he’s in, no matter what ideology you shout as you clamber over the gunwales.