Seems like you had a busy schedule ;) About the subway ticket thing: You barely get checked on the lines, but occasionally they close down single stations and check all people leaving the subway, with police support (and once you're on the escalator there's no way out).
Have a great summer Steve!
It's always a risk to not have a ticket, but as tourists we wouldn't chance it. I've done fairly long trips in the UK where I never had to show my ticket, but I still had one. For subways I'm used to the London one where there are barriers everywhere, but I've been to a few places that have less.
!BEER
Cheers Steve, and Thanks!
Indeed, in that way vienna has really 'public' transportation :D
I remember a Bass player i used to play with. He notoriously had no ticket. So once in a while he'd show up for rehearsals, covered in sweat from running from inspectors. Good ol' times, lol.