One would make the argument they had no choice in the matter same as being born in to a race.
So basically it's constitutional protections of religion vs constitutional protections of a protected class.
You're making the argument that religion should trump protected group and have the right to discriminate despite also being against the law.
I happen to agree with that, even though I think it is antiquated and bigoted. Because nobody should be forced to act against their will. And not recieving a cake, or wedding in a certain location is not forcing an action outside of finding different venues.
On principle, I side with you. Morally, I dont understand refusing to serve people because of their sexuality. And believe if a religion teaches bigotry, there is a fundamental flaw somewhere that should be reconciled.