When I used to work maintenance in a parking garage, they regularly did it in
out of the way places, or the elevators. I'd guess alleys are a good solution too.
Micky D's and the like work when they're not locked. Sometimes they will buy a coffee
or cheap food so they can crap. Bus stations are another option, as are public parks.
Life is better for everyone when there are public accessible toilets.[size=78%] [/size]