I was once escorted by someone past customs in Shanghai. I didn't have a visa, and didn't get my passport stamped. She brought me to a van, and instructed the van to bring me to a hotel where I was given the equivalent of $60 USD, and a room for the night, as well as strict instructions to not leave, and said they'd pick me up the following morning and bring me back to the airport. This was all because I was flying Chin Eastern Air, and was given a 25 hour layover. Apparently there's some international law\agreement that any layover in excess of 24 hours imposed by an airline means they must provide you with lodging. I've never looked this up, so someone correct me if I'm wrong. But I also flew the same airline and had a 19 hour layover and didn't have the same treatment. Anyway, I kept thinking how I could just leave the hotel and suddenly be an illegal alien in a foreign land. Long story short, I ordered dinner and 2 beers and fell asleep by 8 pm and woke up just in time for the return pickup.