Gotcha. I was thinking of the bigger stuff you'd see on lakes -- offshore powerboats, etc.
Sounds like a combination of factors, really. Primarily not much land that's good for it, and the land that is good for it was long ago developed for commercial interests. Makes sense, since this area has been very populated for awhile; the places where people build waterfront houses tend to be lakes that were 'discovered' or at least populated later.