Honestly, I think our culture has reached a decent balance, where we generally accept whatever people do behind closed doors, so long as they thought about what they were doing and were self-aware enough to know that it was right for them.
I had a casual sex buddy for a while in college. I told my friends about it, introduced him to a few even, and no one ever said a thing about it. Honestly, it's not that they didn't care; they just knew that when I was working two jobs and taking classes full time, I didn't have a whole lot of time for relationships and I desired the stress release that sex provided. I never felt judged for the fact that I just wanted sex, and I got it.
I know I'm not sex-negative, I'm fairly sure I'm sex-positive. Basically, I'm all for people getting it on whenever, as long as what they're doing is safe, consentual, and conscientious. Being sexually self-actualized is important, and once you've taken the time to understand yourself, your motivations, and your needs, there really isn't a whole lot limiting you but your own conscience.