I've walked out to this scene when leaving from work at least half a dozen times...
Which resulted in my having to call the cops who subsequently call the tow company. Usually takes ~15-30 minutes for a patrol officer to arrive and ~10 minutes from their arrival for a tow truck or trucks to show up.
I live about a block from a local state college and this usually happens at the start of a semester. It's really annoying and I ALMOST feel bad since the students end up having to pay for (a) a ticket for blocking my driveway and anything else the cops see that they end up writing the vehicle up for, and (b) somewhere a bit north of $100 to get their car out after towing and storage fees. Then again, they need to learn to open their eyes...
I also worry about someone getting pissed and trying to retaliate since I had them towed (even though its pretty obvious its their fault), but thankfully it hasn't been an issue.