Exactly. You generally don't have too many unsupervised youngsters bored with time to kill and bad ideas to pursue. The drinks there are adults with responsibilities who generally aren't looking to make trouble or get fired form their jobs for being delinquents.

I studied at a university which is connected with a driverless suspension railway [1].

Students aren't unsupervised youngsters with bad ideas as such but not far removed from the concept. The H-Bahn never really looked bad.

[1] https://en.wikipedia.org/wiki/H-Bahn

Different societies and cultures. Japan would also _not_ have this problem --while Brazil probably would.

Our society is new and in flux. It hasn't yet converged and congealed with a semi monolithic identity (even if from disparate parts). Who knows if it will ever happen. Maybe one day.