I've seen this also on I-75 in Michigan some years back.
It was not amusing since the boat launched into/on top of
its tow vehicle which rear ended another vehicle in front of it
causing a fast stop..
One other nauseating sight in the FL Keys was a 22' outboard
lying on its side on asphalt after rolling off its trailer in the
middle of an intersection from the tow vehicle making a fast
turn.
And, yes, neither above boats were secured to the trailers with
tie-down straps. I'm sure the drivers thought "I don't need'em".
Aye.
Grandma used to say, "You'll see folks who are penny wise and
dollar foolish."