Whenever you're having the conversation about expectations and monogamy/fidelity type stuff. Usually that's when you go from casually dating to committing to being a couple.
It is something you should mention. When you make assumptions, I've learned the hard way.. that someone should be fine with this or whatever.. it rarely goes well. I really think its super important to talk about like, porn habits, camgirls, masturbation habits, what type of flirting is assumed to be ok/not ok, what kind of contact with ex's is ok.. etc. It's important to know and agree on boundries, and then stick to them. My parents marriage works because they know the boundaries. The boundaries seem insane to me (flirting, porn, etc would all be a no-no) but they are committed to each other and to their boundries so ..their relationship works.
As to whether you 'should' be ok with giving them up or not, i'd argue that maybe it's a sign of incompatibility if you have vastly different views about what is and isn't cheating. If you think it should be cool to visit any kind of sex worker, and she thinks camgirls and stripclubs are ok but no full service sex workers.. then that might be easier to compromise on. But if she's gonna slap you for looking too long at a fitness commercial (Duke's ex wife did this to him) and you like to go to strip clubs and take camgirls private.. that might be a red flag.