That isn't being "smarter", that is just delaying and encouraging the inevitable.
The only way to stop tyranny is instant and obdurate defiance of it. You must fight back when it is small, because when it is large, it will overwhelm.
You let them force you to bake a cake or take a picture, or even say "hello" to you, and they will move the goal posts again later when it suits them.
I hate to see good people losing their businesses over this kind of thing though. I can’t personally afford to be a martyr as I have bills to pay so at the end of the day, I would just bake an obviously substandard cake, call it an accident, charge full price anyways, and go on with my life without any legal hassles. To each their own though.
Well you are dealing with an implacable bunch of people to begin with. You can at least cite you attempted to remedy the situation the best way you could.