Yeah, I say that some of your assumptions may not be correct.
As for vehicle leases, most American individuals buy, unless it's for a business. (Also, the leases in the U.S. are quite different in the U.S., but that's a whole different discussion.)
Europeans pay quadruple what Americans pay for gas, and it definitely affects their transportation choices. Also the fact that they have a choice with pretty good and comprehensive public transport plays into it.
Housing is a bit more complicated. You can only live in your family's home if you stay in the same location, and Americans have been a lot more mobile for generations. Freedom of movement has been really high, and employment has been plentiful. (Mobility has been increasing slowly within the European Union. )
As for your charter, it probably depends on where it is, the type of boat, and also where and how you advertise. I have a friend who charters his boat in Greece, but his clients are mostly American. Because that's who he advertises to, and a lot of it is word of mouth. But I don't think you can accurately assess the U.S. economy based on your charter clients. As an example, when I travel in Europe, the guests at a hotel will likely reflect where that hotel directs it's advertising. I've often stayed at hotels where the guests were consistently of a particular nationality, as I don't always use exclusively U.S.-based search engines.
The American economy has been going gangbusters for a few years now, and exchange rates are better than they were a decade ago. So if it were economics, I'd think there would be a lot more Americans hitting the cruising circuit, but I'm not getting the impression that's the case.
We do actually get internet in the West Indies and I have read nothing on it that substantiates your statements, however, if you'd like to post some links I'd be glad to read them. I must say I am very happy that I wasn't an American airline pilot, steelworker or vehicle assembly worker.
I only post from my personal experience, which is indeed limited in this area. From that experience the vast majority of Americans I know who have late-model luxury cars lease, whereas I know no Europeans who lease, and in multiple days of sailing together the topics of housing and vehicles do come up frequently.
We have yet to advertise anywhere in Europe, and, if you reread my post, I said inquiries, not customers. Most are now coming through TripAdvisor. If Americans aren't smart enough to use that, then that's a whole other discussion.