For example, the Fort at St. Augustine, FL where many lower tier rides start and terminate, the policy is for bicycles to park in the parking lot which appeared to me to be an open invitation to thieves. After spending time talking to the Park Ranger, he looked around for his boss, winked his eye and told me to park it on the side of the ticket station up near the fort which made me feel much better. I was able to go inside and spend some time checking things out.
The NASA Visitor Center at Titusville, FL was not so friendly. They wanted me to park in the motorcycle parking lot which was out of sight of the center entrance. The place is set up like an amusement park and the line of ticket kiosks act as a barrier to anyone sneaking in. I asked if I might park my bike just inside the center where there was an unused wide open area. This felt pretty safe to me being inside the gates. They would not work with me at all on the situation and I had to ride away without being able to visit the museum. I had gone miles out of my way on dangerous no-shoulder roads to get there and remember well the way I felt.
In Philadelphia, PA I wanted to see the Liberty Bell. A Park guard stood there at the entrance where there was a long line to get in, but he wouldn't let me park my bike near him even after I explained the value of all the gear and my plight.
This sort of thing happened a lot. One can lock his bike, but not the gear on board, and I carry lots of stuff. This year (2014) I am attempting a ride through the Pacific Northwest. As I plan my trip, I'm going to write to the places of interest and explain my plight. Maybe I can get some better cooperation that way.