If I’m not mistaken, Harvard’s sailing pavillion on the Charles River is a floating structure so they do not have to pay taxes to Cambridge. I believe MIT’s is a fixed structure with an attached floating dinghy dock. I’m not sure which is older, but this is not a new concept.
There are also several casinos that got around their states’ gambling laws by building on a permanantly-docked boat.
Hmmm, maybe I can get around the building permit requirements that way . . . I’ll have to check.