Smoking and drinking are expensive (and not in terms of healthcare but in 'running costs') too..
I don't smoke and I try not to drink TOO much (and sometimes succeed) so running costs are fairly low. However, some have done the calculations and if you take those two to a higher level, you could be buying a lot of glass for that.
I went to a horse showjumping event with friends who were participating recently, and received a few comments on the huge setup slung around my neck. It did occur to me to ask how much is the acquisition cost of a horse, and the answers I got ranged from the cost of a 350D with kit lens (for entry level horse, too) to a pricetag that would buy a decent 4-door sedan, new. And that doesn't even account for the infrastructure (gotta house it, gotta transport it, gotta let it stretch its legs), the upgrading costs (you can outgrow one, incidentally, if you start small), and the operating expense! Not that there is anything wrong but I jokingly said "Look, I don't have one, so I can afford a bigger camera"
(basically, to each his own.. I spent a lot more on this, but not on other things
)