Pink lighting and classical music is the answer.
The male line of my family at one time or another have all been coach drivers (there is a difference) who have occasionally done bus routes.
The firm we used to work for had a couple of council subsidised services that the main bus operator, Badgerline now part of First had given up claiming they weren't commercial but mainly due to the number of pissheads who travelled late at night. One of these was the last bus at about 11pm from Bristol to Portishead. This was back when pubs shut at 11. You never took any money and just passed Badgerline return ticket. Usually you got one of the older very basic coaches that only came out when everything else had been used because it would come back strewn with chip papers, curry cartons and even a used condom. One night my dad drove it and for some reason the vehicle he had been allocated while several years old would have been a luxury vehicle in it's day. Trapezoid windows, couple of tables with lamps and little floral decorations. The muted lighting cast a pinkish hue and he had Radio 3 playing. The effect the pissed/stoned punters was amazing. Not even a dropped bus ticket to clear up.
(jvz, Thu 2 Jul 2009, 9:01, 3 replies)

Music
They've been playing classical music at Tube stations, I believe, to help nip potential antisocial cruntery in the bud.

Apparently it works pretty well!

(*Click!*)
(5150, Thu 2 Jul 2009, 13:05, closed)

Badgerline?!
!
(redshoes, Thu 2 Jul 2009, 13:20, closed)

I'd have liked to have been on that bus :)
*clicks*
(Professor Kenny Martin Hmm? What?, Thu 2 Jul 2009, 13:39, closed)