they use it as a "VISA" to come over here.... i doubt they can 100% promise to stick with thir Sg husbands through thick and thin....
i have heard of people who aren't that well off... but they bought brides from China for a certain amount... initially those girls just made do with them.. but later on when they realise there are better stuffs out there... off they go....after a few months, they run off with other supposedly better or richer guys who can give them better lives.
$1 is just a stepping stone......

I hope its only the minority though.