OneStepSideways Breastfeeding groups do not exist so that men can learn to accept breastfeeding as normal, they exist to support women who are breastfeeding and finding they need support, usually with technique.
If women are put off going to these groups because men's desire to attend them over rule the women's needs to have a women only space, then there is the potential for women who are struggling with bf to give up - fewer women breastfeeding, more families in which breast feeding is not the norm and fewer children growing up with the idea that breastfeeding is normal in our society.
I breastfed my babies everywhere too, and I was unusual then back in the 80s, but only once I'd established breastfeeding.
In the early days I certainly wouldn't have wanted to sit in front of a lot of strange men at a breastfeeding support group trying to get to grips with the trickier aspect of the whole thing.
I remember, when I had my first baby, sitting in the nursery of the maternity ward struggling to breastfeed my new baby while the nurses sat there feeding all the other babies their bottles and totally ignoring me.
Back then there was no support, apart from National Childbirth Trust groups, for breastfeeding mothers as we were considered an oddity, and tbh, a bit of a nuisance.
However, I stuck it out and went on to breastfeed all three of my children. But oh how I could have used some help and support in those early day, but I certainly wouldn't have gone to a group where men were present.