doesn't seem weird at all. If my husband (who doesn't have "regular" work hours) CAN go and be with the kids with me, he goes... always. He's just involved as I am. He has heard IT ALL about women stuff!!!! He was there for all four of my births, and he could probably answer ANY question about pregnancy OR breastfeeding. I was very open with him (well, he's my best friend, I tell him EVERYTHING), and he's very involved in all the baby stuff. My friends are very laid back moms. They have breastfed in front of him (still, with a cover over them...) and my friends and I don't mind talking girl stuff in front of him. He isn't too crazy about it, and would rather NOT hear it, however. LOL. we DO have four girls, though... so... he's gonna definitely have to get used to it!
I also had another thought: maybe she likes having husband there so she CAN talk with you without having to watch the kids every second. I like having my husband around wherever we go with the kids because it is like having backup "help".
Also, as another mom points out, you don't HAVE to talk about things you don't feel like talking about in front of him. BUT, I'm sure he's heard/seen it all like a lot of dads, and they may not like it but it's really not a big deal...
...and "weird" is not at all how I'd describe this. For one, why is it weird to work at home?!?!
*****ADDED: I find it WEIRD that some other dads DON'T want to be more involved... and that their wives are OKAY with that! I'm glad I have a very great equal parenting partner! I couldn't imagine it another way, nor would I ever accept or want it!
ALSO, a "girls" get-together is different than a play date with your kids. When you plan a girls get-together, usually that is without kids and without guys... "play-dates" to me are welcome to "parents"(and the kids of course!), not just only moms.