Just because you are forced to interact with immoral things that doesn't mean they suddenly become moral.

Libertarians who think taxation is theft still pay taxes. The local restaurant owner will pay the local goons their protection money - shockingly without thinking the protection scheme is a moral one. Many people buy goods manufactured in China, even if they don't support Government oppression (at least not to the extent that's going on there).

Humans are complex creatures. You can disapprove of something while still being (more or less) forced into participating in the activity, without imploding in a puff of logic.