2BNTV:
Not completely sure, but pretty certain that leaving any vehicle overnight is a No-No.
Will it be safe? Probably, unless you leave the Crown Jewels on the floor!
Towed away? I suppose that's certainly a possibility. There are certainly many auto towing operations around, but the only probable cart towing outfit (an advertiser on TOTV) may not necessarily respond to some middle-of-the-night call from some "authority!"
Best bet is to try to avoid leaving it. If your scenario of getting sick merely means getting a ride home, somehow, I'm betting a neighbor could help you retrieve. Depends on the hour, of course!
SWR