The whole point is that it IS related. Country club settings are historically a bastion of racism, and there is a modern corollary here. I think the burden falls on you to prove its not related.
Btw, what do you call "ethnic prejudice" when it's not race-based :
like Muslim semites vs Jewish semites or Protestant whites vs Catholic whites (Irish, Latinos)... and I'm not sure that religion is particularly important for the last two ones where the US is concerned?
https://www.logicallyfallacious.com/logicalfallacies/Proving...