My eye-rolling has to do with the fact that the shuttle bus goes across the street, a 10-15 minute walk. If they offered free parking, I would understand that a non-guest might park there and go to the airport. Otherwise, I don't see a particularly compelling reason to check people's names against a list of guests. I haven't experienced this at any other aiport property in the US.

I actually walked between the hotel and airport 2-3 times during my stay, but perhaps I'm used to walking. Of course, I also walked from this property to the convention center -- took 45 minutes, but the weather was good, and the route took me along the water. I don't know of any shortcut, just kept my eye on the destination and walked toward it!