It was from you Chase that I learned that men used to chase down women for marriage in the west some 30-40 years back and that only lately its changed and shifted the other way to where women now try to pin men down for marriage.
Feminists can be pretty laughably nonsensical… I think like any other dogmatic fundamentalist group they’ll just naturally gravitate towards adopting whatever their mass group claims to so strongly to believe in and follow that because “they're feminist and of course they should be believing in that!!”.
There’s a political theory called the overton window
http://en.wikipedia.org/wiki/Overton_window which says that a political theory will be limited to a narrow window of a range of ideas which the public will be able to accept (and anything outside of the window won’t be able to be accepted conventionally just yet; the theory also suggests that all political radicals are just trying to push open the overton window further).
To give an example: if we were to say that dolphins have intelligence comparable to humans and all dolphins should get to vote, it would be ridiculous … but then it would shed light on dolphin rights and suddenly yes it still wouldn’t make sense for dolphins to get to vote, but it would be paramount then that dolphins get fair treatment and aren’t abused and get far more rights than the “incredibly limited rights they get right now” and so on…
Feminists wouldn’t really get to complain about polygamy until polygamy gained more potential to become mainstream in western society (mainstream over the current norm of everyone expecting and encouraging others to get married).
Then feminists would be able to say “hey why can’t we be polygamous, they're doing it in the Middle East and it’s going on fine!”, and they’d find all the selective facts they'd need to back it up.
I think it never really ends up being a question of what would be best for the people (with any of those groups) as much as it ends up being promoting what the political agenda would be and strictly adhering to it, continually pushing it further and advancing the fundamentalist group’s interests in that way.
EDIT: I just realized you had said western governments are against it... my guess as to that would be that western governments wouldn't really be up for it till they could hash out what the tangible benefit/advantage of doing it would be for them (what the benefit would be, and again if it would fall into the window or not; example here would be women joining the workforce, which the government eventually backed for the opportunity to massively add to the tax base).
What would be in it be for them though? I'm not sure... maybe you know the answer to that Chase?