I don't agree with the primitives solution of lying, but I think these situations could be handled better on a case by case basis. For example with wedding photography, let them know you never decide these things until you meet with the couple to make sure it will be a "good fit" since they only get one shot at having their wedding pics done correctly. A couple of fags show up, you politely go thru your routine and a few days later let them know you won't be able.
Besides, I have to believe there's a network of "acceptable fag business establishments" that are passed around within that group, so the likelihood of this happening is almost seldom.
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