Can they quit baking cakes and go into some other line of business? Then they're not slaves.
Try to put yourself in the position of someone who has principles, counsellor. I understand this can be difficult, and that that is an occupational hazard, but for these people there are simply things they will not create and that they will not do.
Are there cases you won't take? Could any of those be presented as 'discriminating'?
I realize a significant amount of lawyering is just making sure the appropriate blanks get filled in, the 'i's are dotted and 't's are crossed, etc., but imagine that there is something you just won't do, and someone comes in the door and tries to hire you to do it. It isn't illegal, but it so offends your sensibilities that you just won't.
You get sued. You are free to find another profession, too.
Don't you have the right to decline the case? to recuse yourself?