I didn't figure anyone got towed.
All I was saying, was just in case you do live there for extended periods of time, you're kind of playing with fire if you're messing with the management and not technically on the lease. That's the extent of my point. Stuff like this can escalate pretty quick depending on the temper of the people in apartment management.
Most apartment complexes I've had to deal with were pretty cool, but from what you've suggested, if your girlfriend is the one calling to pay for a second parking space and they're getting all anal, then it sounds like you're dealing with a bunch of prudes. And in that case, messing with them like that could easily escalate the situation.
When dealing with prudish or anal apartment management, I always enjoy seeing them get worked up, but seeing as how it's your girlfriend that lives there and not you, you could be causing a sticky situation. If you don't think it'll happen, then by all means, continue to play games with parking spaces. But don't say no one warned you