50k is peanuts compared to what you have to spend on a Chinese bride.
Nonsense. Men don't pay out a dowry to their wife's family. Sure, you need to be able to treat someone right, but women are concerned with future prospects, not what you have in the bank.
And why wouldn't it be a solution? This is a great example of the Market solving social problems!
Okaaay. You do realise that women aren't goods to be bought and sold, ergo they do not form part of the Market, right? You might want to change your tone a bit (sounding a tad chauvinist).
Let's look at the facts. Within a decade there could/is likely to be 25 million Chinese men short of a bride. Given that they're almost certainly going to be amongst the poorest men in society, are they really going to have the income necessary to attract and keep foreign brides? Even if they did, they would require 25 million women to want to move to a new country, learn a new language, etc. That's going to be virtually impossible, unless China suddenly jumps to the top of the standard of living tables.
Then there's always the chance that India might want to get into this game as well. So we're talking way more than 25 million women from a continent which also favours boys and will not exactly be seeing a surplus in eligible young women.
I'm also pretty sure those guys don't buy a huge billboard ad on a street corner!
Companies breaking the law advertise their services all the time, but I was mostly being sarcastic. Assuming that this isn't a bit of a scam in that the company takes most of the money, do you think a happy marriage is going to be formed if it comes about because the bride's family gets a thick wad of cash?
Generally speaking I'm very sceptical of companies that charge people to arrange foreign marriages. Introducing people to others is one thing, but effectively saying "we'll get you a bride if you put money on the table" suggests to me that the other person is not interested in love or has a very naive concept of what it is. Maybe I'm wrong, but I have a feeling that these companies will not want to refund their customers just because the chemistry isn't right. They'll try to organise it so that a marriage will happen. Chances are they'll get poorly educated and/or young girls that don't know what they're letting themselves in for and woo them of promises of a good life, money for their families (as you suggested) and maybe even visas so that their family can move with them.
Whatever the promises, it could easily end in tears. Foreign marriages can be very difficult to maintain, even when people have good lives. Family ties in Asia can be very strong. I saw this myself when a Chinese friend went back to China despite the fact she was in a loving, firm relationship with a good bloke with good prospects. She just couldn't handle the idea of working in a foreign country away from her family any longer, despite the fact she was educated, modern and had prospects herself where she was. Sure some people can do the living overseas thing, but thinking women from Vietnam are all go-getting adventurous types looking to cut all ties is wishful thinking.
And if these companies are targetting better educated, wealthier Vietnamese women looking to marry middle class Chinese men, then we're talking about men who probably would be able to find a Chinese girl but want something better. Poor Chinese men still wouldn't get a shot at getting a woman because the available women would assume there'd be something better.