I feel your pain, and unfortunately, I don't think there's any cure outside of just figuring out a way to get gigs in more happening places.
I feel incredibly fortunate that I'm in a band now that only plays the A rooms in my area (meaning they're always packed - by the club, not us), but I say that with all due humility as I've paid my dues, many times over. Only reason I'm in that situation now is because I got into a band that was already there. Building to that point on my own, doing covers, has never happened.
I don't want to add to your rant, but what sucks is that I know in retrospect that all of the begging I did for decades to get people to shows was useless. At best, we'd get maybe 30 people to show up (and that was rare) - and even with that, if a club didn't have it's own following, it would be a bust. The best that would happen is the club would give us another gig, we wouldn't get the same amount of people, and then they'd either short us money, or they wouldn't ask us back.
I know this sounds incredibly negative, and there are I'm sure exceptions to this rule - but I think the up side is that it might be best to accept now that dragging friends to shows isn't the best way to secure better gigs. There are other ways. I just don't know what they are

... As I said, I joined a band that was already there.
Getting tight and polished enough to get picked up by an agency might do the trick. Making friends with the right people and talking your way into happening spots? Taking crazy pay cuts until you get where you want to be? Or just get creative, and come up with something nobody ever thought of yet

. I believe 100% that where there's a strong enough will, there is a way.