Ahhh, am I the only one annoyed at this?

It's omegaverse... The rules are different...

I read in one omegaverse that had 2 alphas marry that the one who bears the first child is called the wife and in upperclass alpha families it its decided during the engagement so the alpha can plan work around it.

Omegaverse is just an excuse inside the yaoi world to make even more girly ukes. Most are almost like a woman with a penis, they act like one, physically resemble one and can be pregnant too. So being called wife is just a part of this whole ordeal

I know many omegaverse with tough badass omegas as well. I think the thing omegaverse does is more to break down male/female boundaries and set up new ones based on the alpha/beta/omega gender.

Well can be that too
But yaoi is a manga genre made mostly by heterosexual women to please other heterosexual women. And most readers, besides reading about homo couples, prefer heteronormative ones, as the “bottom” behave like and resemble a woman and the “top” is the macho muscular one. I am not saying all are like this, but we can agree the vast majority is.
And Omegaverse (a sub genre of yaoi) reinforces even more this vision, as the “bottom” is even called “wife”, not “husband” besides being a cis male.
I am not demonizing omegaverse, I also read it because all the pheromone stuff is interesting, I am just explaining my view of the reason for this wife thing. It is just a matter of supply and demand, most yaoi readers ask for heteronormative couples, so that is what the mangakas give us

True, perhaps most do, I do not though. I also like omegaverse for the pheromones and the bonding, but my fav Yaoi is a seke couple like in Embracing Love [Haru wo Daite Ita], which is also an old and vastly popular manga.

It being an omegaverse does not excuse it. Mangas don't have their own rules, the rules are decided by mangaka thats about it. Its 2019, we don't have to call the guy who is buttoming a fucking girl just cuz he likes its up his ass. Excuse me, I know a lot of stright man who like a good prostate orgasm.
Sure, this is omegaverse, the omega is basically a guy who can get children, something that a lot of homosexual man would love to be able to do, but damn this still does not make him a WOMEN and a WIFE. Last time I checked, an omega was a guy and not a guy wanting to be a women.
Its about gender based names.