The only reason to buy VIP tickets is for the improved washroom facilities. You get proper bathroom trailers as opposed to porta-potties or Hart Plaza's limited rammed washrooms. To me this makes the tickets worth it. In reality though they are simply a big cash grab.
Once you're in - you can't leave again?
You can come and go as you please.
Great to know! I've been warned that cops will pull you aside and question. No biggie.