Hi snowflake, and welcome!
One thing came to mind when I read your first paragraph... a visual of a large pile of snow, balanced very precariously on a steep slope, until one final flake landed on the pile, and it all tumbled.
Sometimes one person- or a small group- CAN make a difference. (I believe in the "tipping point" environmental theory.)
The snowflake analogy DOES become important, if you throw in the concept of "free will".
Most every other snowflake falls where it goes, without thought -- without direction -- it goes with everyone else into the 'we all need to reproduce' snowpile. They start their own avalance -- and get noticed because of their sheer numbers.
Those who are CF see the big pile of 'breeding-desiring' snowflakes and don't want to be part of them. We have to be as always, so we can only nagivate ourselves to the fringes of the snowbank. We gather, but since our mass is a lot less, we don't get noticed, we don't form a big noticable avalanche, but we do stay away from some of the influence of the breeding-desiring' folks.
The Parents By Choice (PBC) people, also see the mass of those who reproduce "just because", and dont' want to be associated with those people -- so they try to separate themselves from the mass in the middle. They do what they want in their own part of the snowbank. These PBCs are a stronger force than the CFs, have interactions with the 'breeder-desirers without thought', but do their own thing.
To decide which part of the snowbank the snowflake lands on, you have to think, analyze and see the future -- and make the choice for your own direction based on that. If you don't think, you just join the big herd in the middle, and do what everyone else does, not necessarly for your own good.
How's that for an analogy?