Polyamory is relatively common in science fiction fandom, though I think it's common more by contrast with the mainstream society. [1]

Possible status implications: Fans get status by not being like non-fans-- specifically by pursuing some kinds of pleasure more than they do. Or it might be affiliation with Robert Heinlein, in which case we should see a generational effect.

Null hypothesis: Fans aren't more likely to be polyamorous than non-fans, they're just less discreet about it.

[1]Fandom seems to have a lot of pagans and libertarians. Actually, as far as I can tell, neither are all that common.

This is reminding me of a bit in a Samuel Delany essay. This was written some decades ago-- he mentioned that he was apt to overestimate the proportion of women in a crowd.

It seems to me that seeing how accurately people can estimate the proportion of various easily identified groups in a crowd could be a test of background levels of prejudice.