It is not about being "showy", it is more about having the best available. Why not have the new S-Class Mercedes Benz, if you can afford it?
But, people who are "comfortable" money-wise tend to buy smart. A new Mercedes Benz can look "showroom new" for five years to the untrained eye. Truely rich people, just want the best. Why fly Business when you can fly First.
Re Jay Leno: he is more of a car fanatic. He has over a hundred cars, of every shape and type, except interestingly enough, Ferraris. There are many very wealthy car fanatics such as Rowen Atkinson, Nick Mason (from Pink Floyd) and Jay Kay (from Jamiroquai) who are fortunate enough to be able to indulge in their hobby.
I am still saving for the Pagani Zonda that is sitting in the window that I walk past twice a day.