In Munich, last Saturday over 2000 people came to drink their last alcoholic beverage on one of the city's S-trains. To say (drink) Goodbye, so to speak, before the new no-alcohol policy would be implemented on Sunday, the day after.
The party-goers organized themselves via FB and the intention was for this to be a peaceful event, just like it had happened in Hamburg before. However, while apparently turning into a great party, the peaceful bit didn't quite work out. In the end, some 50 trains were damaged and some disturbance was caused for none-celebrating travelers.
The ban came in the first place because of travelers feeling disturbed or even partly unsafe, with violence increasing around train stations. It is valid for inner city and close distance trips. Long distance traveling is not affected.
Do bans really achieve their goal? Will it be the conducters' job to control all the passengers? Ticket please. No alcohol please. Put that bottle away. And then? Isn't the average train-user just getting herself from A to B anyway and will those who wish to cause trouble cause it anyway?