I honestly do not remember any concerts or sports days at school, so don't remember if my mom turned up or not.
I do only work part time, and DH works from home, however, he rarely is able to make the stuff in the day, since he has meetings etc or stuff to do ( on the opposite side of this his work is generally quiet in the school holidays so he can have them at home, even if they don't go out and about)
I will turn up to something if it is on my day off, since I work 3 days a week, however, if it is on a day I work, I cannot just book AL (as usually I get 1-2 weeks notice) or like last year, when I knew in advance when sports day was, I booked that as a day off, then it got moved due to weather so could not make the new date.
If I cannot make something I tell the kids, and they are fine with it. They know I go to what I can, and are fine when I cant go to other things.
I prefer to keep my Annual leave for when they are on holiday, so I use my AL for Christmas, Easter and the Summer.