>>31992194It sounds like an internet-enabled version of the old Polyandric relationships tolerated in certain Southeast Asian islands. They used to believe that every man who came in the woman imparted some of their genetic material, making the resulting child the product of all of the men the woman slept with. Modern scientific discoveries have killed the cultural basis for this model though.
On the economic side, it's usually done to keep estates and wealth tied together, much like primogeniture law did for European nobles, but for resource-scarce settings. In that case, multiple brothers are married to the same woman (works better the fewer boys there are in the marriage), and they all raise the kids as their own, collectively.
To make your suggestion work: They'd have to each volunteer for a child-support arrangement and agree never to take a paternity test, regardless of the number of children born, but allow these men access as though they were each the fathers of the children, with optional sexual access to the mother herself.
This would allow them to cut most of the costs of raising a child, since men who didn't reproduce would be financially supporting the child of those who did. If 9 men participate and 3 children are born, each man only has to contribute a theoretical 1/3rd of the amount to support them, freeing up resources to be invested in the sorts of financial risks bachelors would take. Alternatively, it could be 9-and-9, and they'd use bulk rearing and a half-brother family model to cut the costs of raising children.
Normally, this would be handled via taxes, but since this perverse union isn't recognized anywhere in the world (as far as I know), you couldn't expect governments to set up a structure for it.
Where this gets interesting is the topic of scale:
Multiple women in this arrangement together would each be able to better handle the children and their needs than a single mother handling 9 men and 3 kids, or 9 men and 9 kids. Additionally, due to the limited involvement of the men in the lives of the kids (by necessity), the children would likely adopt the beliefs and practices of their mothers, primarily. In the meantime, the men involved would begin to view each other as communal partners, working together toward a project's conclusion. If it becomes common enough (deranged fantasy), it may even be a way for certain men, knowing they won't reproduce, to gain sexual access to a woman, if only because it's seen as degenerate for a man to be "unmarried". The mother may select fathers since she has control over the sperm samples and can't be checked. The only thing remaining is ensuring none of the fathers are visually distinct, lest the entire thing blow up when 8 Asian pseudo-fathers see a black baby.
I have no idea what would happen with the surplus women if this actually became somewhat common. At the very least, less women are expressing interest in raising children these days.
TL;DR: More resources per child, or increased efficiency. Also, HOT.