They couldn't impose speed limits on the open ocean, they'd never be able to enforce it. The Coasties have their hands full just trying to stop the drug traffic.
Its all the blowboaters, weekend fisherman and families out with their 15' john boat with a 20hp Johnson that feel threatend by the high speeds and sound levels our boats are capable of.
They look at us the we (not I) look at Jet-ski's. A loud, noisy, obnoxious, reckless bunch of drunken crazies.
Gee, kind of like the biker image from the early 60's.