Not everyone has to live their life the way you see fit. I've given you an explanation of why some people structure their relationship that way, why are you reacting so defensively? Does what other adults consent to make you feel threatened? Why?
It's also extremely different to agree that some amount of extra-marital sex is OK, to being cheated on without being aware. The betrayal of trust is to me the main problem with cheaters.
I don't think you've fully absorbed the point I've made. I agree with your sentence here - but I'd argue that it is a symptom of a societal construct that is counter to our biological reality which one can fix by making it so there's nothing to be found out. If you discuss rules and boundaries beforehand like emotionally mature adults, there's no element of betrayal or breach of trust.
> I would like to you to try to present your point to your wife.
I've been in my current relationship for close to two decades. Not a wife, because we like the idea of being with a person that chooses to be with one every day by their own volition, not by some legal contract rooted in patriarchal control.
While we're currently monogamous, we've went through several phases where we invited other partners into the fold, with the consent of everybody involved. Some of those were even longer-term, multi-year repeat encounters. At no point did it diminish my love for her or hers for me. To the contrary, it's made us appreciate each other more and shown us that our relationship is strong enough to prioritize each other's well-being over our jealous need for control.
The desire to sleep around is obviously a desire to feed your own selfish ego.
This is where I have a problem when people try to defend this. If you’re honest that you like to sleep around and you found a partner that likes to sleep around, fine.
But the I have evolved beyond the quaint social mores of the unenlightened bit is silly.