I posted somewhere on my introduction about this. I think a fast growing segment of polyamory is of the polyfi type, people expanding their relationship to include more people, but in a closed format. A lot of mono people can understand this, due to the economic, time, and fun reasons.
These people run into the "open poly" people that can sometimes be very weird (not that it's wrong to be weird). I just think when you're trying to meet people like you it's not necesarily the best way to find people simply by the whole "I'm poly, you are too, hence we should be friends". Poly is way too broad for that. My advice is to find people that you like, regardless of their "sexual or relationship orientation" and "convert them", if they are open to it, to your values. There are many logical paths to take for such a thing and most intelligent people are responsive to it, they just need someone to educate them.