You hit upon perhaps the solution to the other commenter's issue - scale back to smaller, local (or near local) bands.

Check they local college; they likely have free concerts at their auditorium of a variety of genres, though probably more likely you'll get orchestras and jazz bands (which are great).

I live in a university town, and the free concerts are great. Especially because the students and faculty are most often playing material that I've never heard, including new and experimental stuff.

Over the years it's been hard to avoid noticing that the people who show up for classical and jazz concerts tend to be older. But we're not playing "the music they grew up with." Many of them grew up listening to rock 'n' roll or similar, and when we play an old pop tune, they'll get up and dance.

What I think instead is that they've adjusted their musical tastes to find settings where they can enjoy the performance: Typically quieter, less crowded (though we fill our venues), easier to get in and out of (parking, public transit, etc), and at decent hours.