For one thing
the don't have a big enough footprint to be strong enough
and for another they dont have the necessary welded bale
that is necessary to strengthen them.

Go look at the boat since it's obvious you can't see either. The bases are
bolted thru the deck plus bolted to the toerail. They don't go anywhere.
S/V Express 30 "Ringmaster"
Trains are a winter sport