100% this. ^
Reminds me of when I first came to the area I live in now. A woman about half a mile away from me had created a 'womans coffee and chat group' that she had at her own house. She had a large house, and 3 acres of land. Between 20 and 25 women used to meet and chat and have coffee and discuss hobbies, and do some crafting and painting and drawing, and sometimes 2 or 3 of them would walk around three acres of garden for half an hour.
It was wonderful. She was quite well off and even though she was offered money for people to attend she didn't take it - she just provided coffees, cold drinks, and teas and biscuits ... although some people brought some cakes and biscuits along sometimes too .. it was amazing and a really great safe space for women to chat and catch up. A wonderful friendship circle.
It had been going 3 years, and I had been going for 9 months, and this one woman came after overhearing someone chatting about it. She more or less invited herself. Ooooh can I come?' she asked. Well, most women were welcome, and there seemed no reason to say no, so the leader was asked, and she said 'yes she can come..'
Literally just the third time that she came (it was twice a month,) she started saying 'my Steve would love to come to this - my husband Steve.' It was explained by the lady that created and run the group (and her 2 oldest friends/the two ladies that helped her,) that this was a women only group. So sorry, but no...
The new lady just shrugged her shoulders and moved on. Couple of weeks later - she came, and the first thing she said is 'I was talking to my husband Steve, and he said he really does want to come to this group, and he doesn't like being excluded, and actually you are breaking the law by not allowing a man here because it's sexism!' 
I don't know how the woman and her two helpers/friends kept their cool, but the leader explained gently but firmly that this is her home, and this is a group of friends that she has around. This is not some official government run or council run group ... this is her home and she'll have who she wants in the home.
The woman carried on and said 'well I really do think it's quite sexist, he really should be allowed to come.'
One of the two women that regularly helped the leader, and who she'd known for many years said 'look, if he wants to come to a meet up group like this - tell him to create his own. He is NOT coming to this one. No men are coming to this one. This is a woman's friendship group ... So him - and you - need to stop trying to push him into coming here, otherwise we're afraid that we're going to stop you coming. We don't want to ban you but we will if you keep on with this.'
This woman came a couple more times (don't know how she had the nerve to show her face tbh,) but most people were quite offhand with her after that, because they were so disgusted with her, so she didn't come after those 2 times.
Yes I KNOW men are allowed here, but that doesn't mean some women aren't allowed to feel uncomfortable with it, or wish they wouldn't come here.