Quite arguably, neither are you - there is a huge difference between actively pushing for change (lobbying the state legislature, organizing a grassroots movement, petitioning, etc.) and simply "bucking the system" by not tipping. The former requires a lot more motivation, namely caring about the servers' wages enough to put in that work... from your statements, it would appear that you don't really care whether servers are underpaid or not, but rather only about not having (or being expected) to tip. And, while I disagree with that sentiment, I can't fault you for it... but please don't couch your refusal to tip as a "push for change" - you aren't pushing for change, you are simply refusing to participate in a voluntary system.