The rules are there to prevent systematic descrimination on something you can't really change (well you can change religion, but that not normally considered easy). It's usually gender, religion, etnicity and disabillity, but can also include LGBT, transpersons and age. If worst comes to worst, you can shave, they don't have that option. One or two places might not matter much, but all of them?
Nah, it's rejecting the service because they are gay that's illegal, not the service itself. It would be the same decision if they choosed to not photograf them on a special holiday, a family photo etc, etc, only because they were gay and would do it for straight people.
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