Having an education in biology and physiology, I'm far too aware of the delicate nature of the intestinal lining and such...that stated, I find anal play to be a pleasure, but one I prefer to occur occasionally so as to not take the 'shine' off it. Anal sex though...no, I'm far too concerned about possible damage. Master is fine with my Limit regarding that as he feels the same way and isn't too interested in things that could threaten our lives or health in such a serious manner in such an easily-done manner.
YES, many people indulge in it without harm, and we do not judge or think negatively about such--but it's not for us.

As for anal play and enemas, those are FINE with me.