I had no idea you can request to exclude on the basis of protected class. Could you exclude black riders as well as a safety precaution in places where say that demographic has higher homicide rates?
As it is a membership-only club, yes they can: https://en.wikipedia.org/wiki/Boy_Scouts_of_America_v._Dale
This is super offensive.
That's not even as close to as smart of a gotcha as you think it is.