I'm fine with people who hold an opinion on principle. One example is those who believe that ALL businesses must serve the public, even those they disagree with. If held sincerely, they would serve, not only LGBT+, but also Christians, Muslims, Atheists, and those holding firm for Traditional Marriage.
That doesn't often happen. What does happen is that these 'principled' people will fight for the rights of those they agree with, and conveniently ignore the rights of those whose opinions they oppose.
One such person, whose rights are being trampled - with impunity - is Trey Trainor. His case is detailed here.
IF you value 1st Amendment rights, you have to champion all who seek to use them - EVEN those with whom you disagree.