I could see gen-z do it too. They give no fucks, since the world is ending anyway and none of us are rich enough to buy our way into politics and do something about it.
That was a form of detention for us. They'd keep us until the buses had left, then let us go. We had the choice of walking home or phoning our parents. I did a lot of walking in the '70s.
My bus driver left if you didn't make it on time. I say bus, but they were really just vans (Opel/Vauxhall Vivaro I believe) fitted to carry people, because it was a small school and we were all spread out on the countryside. We didn't even call it a bus, it was "school taxi."
My mother didn't have a car or driver's license, and no buses went anywhere near where we lived. There were a few occasions where I did miss the bus, so I had to walk home. Looking at Google Maps it says it's only about a two hour walk. I recall it happening in the winter though, lots of snow, and me being fairly young (around 9 I think) I didn't get home until half past nine in the evening haha.
We had a bus driver who'd drive away if he had already closed the doors, regardless of if he could see you running for the bus or if other students would tell him someone was coming.
Smug little prick used to whistle like a fucking 1950s Disney character while he did it, too.