I've done both ....are you talking j24 's or hobbies ....or bigger ones. Crewing on a large boats is cheap....everything else gets really expensive really fast. Beer can races where always lots fun ....always a healthy dose of drinking and socializing after ...even some fighting. ...drunken sailors go figure.
I'll say they are both fun but are very different from each other ....going 150 down the back straight knowing if you fuck up you're going in the wall is a very different feeling then 10 to 15 knots on a boat. Although hiking out on cats on a rough day in high winds with cold water underneath will get your blood pumping in a very similar manner. Turtleling really really sucks in cold water.