I don't think teaching is any more family-unfriendly than many other jobs. I'm not a teacher but many friends and in-laws are! Their experiences seem to be that the initial few years can be tough, but after that it does get easier, if you're organised anyway.
My sister in law and her husband both teach, one at primary, one at secondary. They never work at weekends and very rarely in holidays - at Christmas for example my sister in law went in for half a day, taking one child in with her, the other opted instead to come and play with my son. In the summer she typically goes into school for about 2 days, and does a very small amount of paperwork/planning from home. She and her husband managed to go to New Zealand for 4 weeks last summer with no adverse effect on their planning and preparation.
My brother in law has had many jobs both in and out of teaching, and he is adamant that teaching is the most family-friendly job he's had - with the caveat already mentioned of it being hard/impossible to get to your own children's school events.
Not getting time off for your own children's school events is indeed a problem, my in-laws are lucky in that they have willing parents who are able to attend many events. In any case, at my own children's school, there are many children whose parents (not teachers) can't often attend school events in the daytime, so it's not unique to teaching.
I do think you must really want to teach and to be prepared to deal with awkward customers (children, parents, sometimes heads!) and a lot of paperwork, but certainly the friends I have who teach manage to combine that with bringing up children and still having active social or community lives. Perhaps they've all just hit lucky with their schools!