The polyamorist community I belong to is absolutely the most accepting group of people I have ever met in many ways.... except for one LOL! A lot of them, and I love them all as much as I love any friend, harbor a belief that veryone has the potential to be polyamorous and that monogamy is flawed. It is my personal belief that it is hard to believe something will work when you either don't want it or can't do it. Therefore I agree with your thoughts on who lives poly either by choice or nature. This isn't a negative observation, but is my experience.
Playing the Game of Life with Monopoly rules.
Monogamy might just be in my genes
Poly Events All Over