> that's not what marriage is/has been primarily about
Ancient societies' marriages we have records about were principally about economics and politics.
Maybe the poor were having love marriages. We don't know because most of our sources couldn't be bothered with them. But to the degree we have evidence, it's in even poor landowners preferring to marry children off to the owners of adjoining plots. Like, maybe that's a coïncidence. But probably not.
Low sample size but two sets of ancestors from agricultural societies that married in the 1920s weren't especially happy together from what I've been told. One of the marriages was definitely a result of adjacent land though in neither case was it child of wealthy person getting married off to child of another wealthy person.
How do you suppose people in those times would even meet some love interest in a far away place, aka the next town over?
I mean, your kids also just didn't travel much farther than your neighbor's plots for the vast majority of their life.
If anything, political marriages are defined by a marriage outside your economic sphere of influence (which for ancient agricultural workers would generally be about a three day journey due to the ox problem), and to someone you don't know. These couples probably grew up together and went to social events like church together from birth.