Your sailing comment is interesting - why do you think the less affluent have dropped out of it?
No surprises, although where I live may bias it a bit. In many ways boat ownership seems very similar to GA, although i've never looked at the bills in detail so i don't have quite the same insight. There's usually someone trying to cut their losses and get out, so cheap boats can be found and it's easy enough to buy in, but berthing charges, like hangarage, are high and it seems to me that maintainance (and possibly insurance) are even more expensive than GA. The result is that the fixed costs haemorrhage money and it becomes hard to justify. Then there's supply and demand. There's lots of money around, as you know. There's also limited space, so attract the big spenders and up go the prices. Fixed costs go up even more, and suddenly you've priced the low end out of the market.
It's all fine from a business point of view, the people who struggle to afford it weren't making you much money anyway. However, it replaces the people who struggle to afford it for the love of it with people who do it to fit the marketing that got them there in the first place. Business-wise it makes sense, but it's not such a nice place to be (edit: IMHO, of course
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