If you have the time to learn, and are mechanically inclined, it can be very rewarding!

Most bike mechanics don't go to school for this stuff (i didn't) we just learned from other bike mechanics. So you can buy the tools and learn too -- which makes you a bike mechanic also :)

Re: brake bleeding specifically, a lot of the mechanics i worked with didn't like doing it, and we had one person who did all of them. I'm not exactly sure but i think it was because the brake fluid wasn't nice to work with (unless you were lucky enough to need mineral oil).