Just off top of my head.

Inheritance - no explanation needed.

personal time - hard to get quality time and Love is can be selfish.

Issues with accidental incest - my dad side loves cheating. I have lots of half siblings and cousins id never meet all over globe. One uncle had 15ish kids that he knew of. So I dont date my dad's race. Nope train.

The dating market - One less wife available for men leads to anger for those without one. This is why I was told gay men are more accepted in certain cultures than lesbians.