Man, you guys just won't let up. What's to be defensive about? Sure a hobby is anything you spend your time doing that you don't get paid for, but not by Mghcanuck's wife's standards. Her idea of a hobby is something you do with your hands or your mind, not your pocketbook. My advice to him is she's right. Save your money.
My hobby is rearranging my speakers. I spend hour after hour with tape measure and spl meter and test discs. Fascinating how an inch one way or another makes such a difference.
Some guys are on an endless quest for old second hand lps in thrift shops. That's a hobby.
Trying to find the cheapest good sound you can get, that's sort of interesting.
But just going out and buying more and bigger and better rated by the buff mags or, worse, online self-styled reviewers? That's not much of a hobby.