On the other hand I've had very positive dealings with the Park Service. Finn & Haddie did a few spots years ago, maybe 3 yrs in a row, at the national park in Salem, Mass. We were hired at an agreed amount to do sea shanties, it was a local sea festival & it was a very pleasant experience. We did something prior to that when a tall ships parade came through Boston, maybe 15+ yrs ago again it was a delight. We also did a stint at the Charlestown Navy Yard (run by the Park service). They were having a bit of a hard time pushing their aggenda because of their relationship with the Navy because of the USS Constitution but they were great & if they had their way that Navy Yard would've have become much more than it is now.
I tried to orginize a regular shanty session on board Old Ironsides while she was in dry dock but only got as far as doing a few under her bowsprit, the Navy blocked any thing that the Park Service & I tried when it came to singing on board. Gotta give the PS credit, they were really up for any musical or other cultural event that would showcase the Old Lady.

Barry