Good is relative. And you could easily rabbit hole on this. Do people have the same sense of quality? Have people changed their rating scale based on production/effects quality? Etc etc. Probably best to just take the subjective rating.
It's far more simple than that. Many men absolutely love sex with new women. Humans are heavily social, and moral boundaries are strongly influenced by those that surround them. It is much easier to break certain moral boundaries when those around you also break them, and this gives men an opportunity to fulfill their desires.
> Respecting monogamy, at least in America, is one of those things: regardless of how we naturally would like to behave, we are expected to (and promise to) respect the sanctity of marriage.
When did residing in a particular nation-state define such specific moral boundaries? Are you saying if I move to China I can cheat on my spouse because that's how things are done there? It seems you are applying your own morals to 300 million members of a very diverse group of people.