I think that you could help them by trying to talk to your friend. I have a friend who's parenting I do not agree with (we have been good friends since 7th grade!!) and because we have been friends for so long it is very difficult for me to comment on her parenting because I do not want to get into a fight with her. But, I try to at least not act like I agree with what she is doing, I certainly make it clear that I do things differently, and hope that she will get a clue.