Out of curiosity, was there ever a time in the last decade where you had to make a living solely by playing music? Or ever at all?
Lots of them won't but some will. There is a vibrant life outside of Craigslist, and there are start-up bands that consist of experienced and talented players. Why would they join a start up?
- Thinks the project has lots of potential.
- Likes the people he/she gets to play with
- Artistic freedom and love of the material
- An opportunity for ownership, as opposed to being a sideman
I've had a chance to work with some really talented players in startups, and even though they didn't necessarily go anywhere, I had future opportunities to work with them that did.
Most seasoned players have been around the block for a while, and usually already know what they are looking for.
Things have changed, man. The cost of living has gotten higher, and the pay for bands haven't. You have to be creative to eek out a modest living. If $100 man is decent pay for a gig, and $40K is a decent salary, you'd have to do 400 gigs a year to make that. It's very difficult to do that with one band doing bar gigs. Especially, when there are almost no places that do paid music more than 3 nights a week.
So if a band is only down for gigging 2x a month, then there's no reason to not fill the gig calendar 2x a month with that band and then fill up my calendar with other gigs from other acts. If a full gig calendar is what I'm seeking, I'll at least check into something before writing it off, because you won't always know what the front door to a great opportunity is going to look like. If there is any place where you shouldn't judge a book by it's cover is music.
As others said, tribute acts can pay well, and once you get the material down, it doesn't take as much practice, so in the long run, it can be a great investment of time. Rock bands with middle-aged and older members can still play weddings and corporates, which pay well. Acoustic gigs seem to be getting popular, so even if one of the bands you check out fails, as long as you get one person out of it that you can gel and jam with, you can play gigs, and possibly make even more per man. If you can get up to $200 a gig, you only need to play 200 of them to make a decent living.

And there's other places for gigs that pay, and one of those losers could be a contact for a church that needs to fill a paid position, or an event planner that regularly books bands. A seasoned pro I respected told me that to check out as many opportunities as you can, because you never know which one will pan out until you actually check it out and try it. At worst, you can make a contact.
And if you're tired of playing Mustang Sally, and butchering another version of Don't Stop Believing, you can join in on an original project or some esoteric genre just for your own fun. I had one of the top sax players in town play with me for a while on a start up Jazz project just because I was willing to play Bop. The project did one gig and fizzled, but we still keep in touch.