Last year in order to save money, my friends and i just camped in my car in the parking lot of a hotel. The only thing that sucked was that you wake up at 8 in the morning because of the sun, but the same happens if decide to go for the campgrounds.
In the morning we would just go in the hotel and get free continental breakfast (cereal, muffins, pastries, fruit etc). We needed to shower pretty bad so we just went into the hotel and looked for a room that was being cleaned by a cleaning lady. We then asked her if it was ok if we could 'shower real quick' in our room before heading out.
Just thought id share some advice. Worked perfectly for me and i saved a couple hundred bucks