One off the most eye-opening things about the U-Bahn (subway) and all mass transportation in Munich when I lived there was that it was all on the honor system. Sure there were spot checks but they were very intermittent and very seldom. You were supposed to buy a ticket, or a day pass or a month pass or even a year pass. But again, on the honor system. If you wanted to ‘ride back’ and risk the fine, you could probably get away with it for months.
Not all but some other Euro cities also use that system. What I am familiar with is in Toronto the subway has ticket takers and fare entry but the commuter trains do not using said honor system.
The MetroLink light rail in St. Louis, MO was also on the honor system.
Can’t say about MetroLink today, but the honor system was in effect in the 1990s when I frequently rode it from the airport to Union Station downtown.
There were spot checks on MetroLink trains. If you didn’t have a ticket, you received a summons on the spot. Saw that a few times.
Spot checks have evolved. If you ride the German Bahn or bus system five times a week to work, you probably get checked at least 3 times a week, and half the time...the police will accompany them.
They’ve come a long way. I remember seeing a sign in the Munich U-Bahn in 1990 that literally (in German) said “Don’t be a ‘N-word’, pay your fare.”
But if you get caught the fine is very high