I’m sure there’s some kidnapped wives historically. Some wives bought from their fathers. But there’s also plenty of women who have consented to marry a man who already has a lot of wives. The issue has to do with resources and political power.

A rich and powerful man has a lot of resources available for his wives and children. A poor and weak man has few or none. Your chances of escaping starvation and death are much higher with the rich and powerful man.

Notice that I made zero mention of love. Marriage for love is a luxury of modernity, of wealth and power overflowing. You didn’t marry for love in the days when a bad year meant there was no food to last through winter.