Those people with kids were once people like you, say 10-20 years ago, and they didn't fully understand the precedent they were setting by accepting and normalising those working practices. I would bet if any of them could go back, they would undo it.
Personally though yes I do expect tit for tat. And there are employers out there that understand this very well. At one of my previous places for example we had a few major traffic days which required a sort of "all hands on deck" for the day and part of the night. You probably worked an extra 2 hours in total but you were looking at the chat and production monitors regularly while going about your day and evening/night otherwise. You got an extra day off for that.
Also for production support via 'pager' any call from the NOC to you, even if it took 5 minutes of you just telling them 'yeah restart service X' was an automatic 1 hour billed at overtime rates.
No not contractors. Internal employees.
Also I do love my work and it's not work in that sense. But that does not preclude me from wanting and working actively towards a proper work environment. If you pay me for 40 hours you get 40 hours. 40 hours of 100% of me. Not 60 hours of 50% of me.
Would I have enjoyed this if I wasn't a 20-something with no kids who who lived and breathed games? No. So I don't honestly expect everyone to understand this either.
If you love your work, it's not work.
Never once did I feel like crunch "wreaked havoc with my life". I think you are imagining the worst case scenario. Sure, it could. And the people who worked there who were parents with kids, I felt bad for them. I don't think I would have made that choice. But for me and many of my childless colleagues, the reality is that we loved working in games and getting that experience was vital to our careers.