> There seems to be a lot of resistance from remote workers about remote worker retreats happening outside of work hours. Is this actually a thing? I have never heard of it other than the weekend caveat (weekend only event with team buy in) that I mentioned above.

The occasional event w/ buy-in definitely can work, but that wasn't how OP seemed to frame it. Maybe I misinterpreted, maybe he badly explained his idea, I don't know. But I'd have given anybody sh*t for trying to make me work outside of work hours, remote or not.