On more than one occasion I have seen Canadian snowbirds anchor off a marina
then, after dark, tie up to an outside slip, hook up their electric, spend
the night then depart before business hours the next morning.

Hey a friend and I delivered his new Hunter 30 back in 89 and we traveled down
the Chesapeak in Nov. and did this. We needed heat.
S/V Express 30 "Ringmaster"
Trains are a winter sport