Then there’s no harm in revealing that fact ahead of time. Just let them know not to expect a tip and enjoy your meal shame-free.
I can tell you, as I’m sure you know, that tipping is expected, even if it isn’t legally enforced. If you truly believe in honest pay for honest work, then be honest about the fact that you will not be subsidizing their pay and relieve them of that conventional expectation. If you’re being honest with yourself, you should have no problem with that, right?