This is true. They will confirm your PS time and then give you a three-hour parking pass. However, when we pulled up on Sunday, we were running late so I decided to drop my family off at the front door and then go park the car and meet them inside. The valet came out and asked if I wanted my car parked. I asked him if I valet parked it would I be able to leave it there for the whole day. He said he could do that for me and that I would have to pay $6 for parking when I came back for the car. I gave him $5 for helping me out (since we were so late). When I got back to the car that evening and went to pick it up, I found that he had also marked me down as already paid .... so I saved the $6.
Not saying that this will always work but it might...