The standard feminist view on mail-order brides is that they are a sign of patriarchy -- that women can be bought and sold like chattel, that there is a power imbalance because the groom is from a wealthier station than the poorer wife, and hence she might be pressured into things in marriage that she might otherwise stand up against.
In reality the mail-order bride is a con artist who pits a crowd of schlubs from the First World against each other. Whoever will grovel and promise her the most, wins. She's a careerist auctioning off her hand in marriage to the highest bidder. She has the upper hand from the get-go because there's an even stronger than usual degree of "lots of dudes competing savagely over precious few marriageable women." Her suitors are drawn from across the world, not just around town. Talk about encouraging a princess mentality.
This power imbalance favoring the woman continues into the marriage, where she wears the pants. The schlubby husband is aware that she's only shacking up with him because he won the auction, and that if she felt dissatisfied with his level of being pushed over, she might have second thoughts and contact the next-highest bidder. Not wanting all his time, money, and effort to go down the tubes, he goes along with her plans -- who else is he going to find at this point?
What groups give us these mercenary, ball-busting, gold-digging women, who fool the schlubs with fake smiles and hammed-up femininity? They are primarily concentrated in Eastern Europe -- i.e., north of the Balkans -- and East Asia, with a decent showing by Latin America. They are absent from Central Asia, the Middle East, and the Mediterranean.
That split points to the role of pastoralism vs. intensive agriculture, and in particular whether the societies are run by a culture of honor or a culture of law. Recall the civilizational fault-line through Europe. Men run things in a pastoralist society, and that includes who is granted access to a given woman. Her male kinsmen make that decision, and you must go through them. Hence the tradition, stronger in the American South than in the North, of asking her father for her hand in marriage. Also recall the international crime statistics which suggest that a culture of honor serves as a strong deterrent to rape.
So, like hell she's going to get to choose whoever she wants. Pastoralists also show higher levels of cousin marriage than farmers, dealing another blow to the prospects of mail-order brides, whose suitors come from across the globe. If she insisted on it, she would likely find herself on the wrong end of an honor killing by the male kinsmen whose authority she tried to over-ride. Or perhaps something less severe but still sufficiently persuasive.
The opposite of honor is legalism. In a culture of law, as long as she's carrying out her transaction in good faith, and continues to uphold her end of the bargain, then who can stop her? After all, it's only marriage: she's not harming anyone else, is she? (In the honor-obsessed culture, yes, she is -- honor is distributed among members of a clan, so that her loss of honor stains the honor of her menfolk as well.)
Her folks probably wanted her to marry a nice local boy, but then she'll probably live better after selling herself to the highest bidder. Agriculturalist societies are the most highly stratified, where money and status are more important than niggling matters of purity and corruption. So, whaddaya gonna do?
As far as we can tell, women in hunter-gatherer groups seem to be closer to co-equals with their husbands, while specializing in different niches. Agriculture, which Jared Diamond described as "the worst mistake in the history of the human race," appears to have bred bossy women. My hunch is that it's because the men and women are now doing the same labor -- stooping over a field, yanking weeds, sowing seeds, grinding corn, and so on. Women lose respect for their husbands when they don't hunt game any longer. And now women are not dependent on men for precious meat -- hardly anyone gets meat at all, and instead both subsist on grains. Shoot, she toiled just as much as he did to put that meal of rice or oatmeal on the table, so why shouldn't she deserve a little more authority?
The same applies even more strongly to women in horticulturalist societies, where they do all of the productive work. (Unless they're white, Latin Americans mostly come from a mix of agriculture and horticulture.)
Only pastoralist women can be said to have respect for and an eagerness to please their husbands. (H-G women are neither complaisant nor contemptuous.) Surely a large part of that is the selection pressure on them to not behave dishonorably in a male-controlled society. Whether from genetic programming or cultural experience, they have a keen sense of what reprisals they might face if they got on the bad side of various groups of related men (her own menfolk, or those of her husband).
Lord knows that women from herding societies are temperamental and headstrong, but the men can be even more so. Asian tiger mothers don't get much push-back from docile Asian husbands. Horticulturalist men don't stick around if they don't have to -- the black dude would just leave rather than put up with all that negativity in the house coming from his baby mama.
But Italian men do stand up, so that Italian spouses can often be seen getting into lovers' quarrels, kissing and making up, and then going through the drama cycle over and over. And Irish men are not unknown to give their willful wives a pair of Irish sunglasses, then apologizing and turning on the ol' Irish charm to keep her around. Life among herding peoples is never uneventful.
Pastoralist babes may be the hardest to get access to, surrounded by several layers of kinsmen scrutinizing your motives and character, but they therefore bring a greater reward in marriage -- respect for her husband. Note: respect goes beyond merely wanting to keep him content, the way that a gold-digger wouldn't want to arouse suspicion or risk killing the goose that laid the golden egg. Women are more child-like and hence not very respectful of others, so finding those who are is no trivial matter for enjoying a fulfilling marriage.