I suspect that if I banned the followers of a religion I found "offensive" from an establishment I owned, you'd be writing a very different post. The problem with the free association argument from censorship proponents is that they've never consistent about it. They're happy to talk up the rights of institutions to exclude right up until the moment that they themselves are excluded.
A functioning society is one in which you don't put your livelihood at risk by agreeing with 50% of the population on a matter of public importance. Violating this principle is tyranny, and I don't care what elaborate justifications anyone comes up with to explain it away. You don't get to try to win political fights by personally ruining regular people on the other side.