The issue is your second paragraph
It's not up to you to decide what your daughter finds pleasurable or not.
It doesn't matter if it's not worth it for you. It's not worth it for me either, that doesn't mean the women who do find it worthwhile are dirty, perverse, disgusting or whatever judgemental shit has been posted on here.
What isn't acceptable is shaming those who do enjoy it. It's also not acceptable to want to keep girls especially ignorant to how to practice safer anal sex.
25% of women have anal sex. There is a strong likelihood that many peoples children will give it a go.
Would you prefer her to know you need to be lubricated to high heavens and your partner has to go slowly to allow the muscles to relax or let the guy she is with who has got his ideas from porn shove it in because neither of them know any different?