If you park in a lot then your car is pretty sure to be fine. Plus I can leave whenever I want. NJ Transit runs less trains on the weekend and taking the Raritan line is a bitch.
Yeah. The Raritan line blows. Last train that heads far enough west for me on weekdays is at like 11pm. Weekends, I'm screwed. Have to take it to Raritan, then drive another 20 mins to get home anyways. Might as well drive. If you got two people, it's significantly cheaper than the train. Freakin' $12 to take it from one end of the Raritan line to the other. It costs me like $12 in gas to drive to Newark, so with a 2nd person, it's all of a sudden half the price of the train.
Re: Parking: Never had any issues in a lot, have parked on the street many times, had a window broken once, sucked, but not the end of the world. Probably less money to fix that than I saved by never paying to park.