Because if this would all be true, I think no rational man would marry under such conditions, ever.

Have you considered making a LW poll to test this? State these facts and ask men whether they would be willing to legally marry under modern circumstances. For extra fun, make another poll a few years later and ask how many men who said "no" in the original poll are now married.

EDIT: Though, come to think of it, this probably tells us more about the level of rationality of the average LW user than about what a truly rational man would do in this situation.