Oh man, we have a place nearby that has easily 40 machines, and some serious classics (they had the Elton John machine with the recalled artwork). They've been around for a few years -- simple setup: $20 gets you a wrist band and you can play for 4 hours[0]. And I think that's the crux of it: I am unwilling to pay a buck a play for pinball only to -- often -- find out that it has multiple mechanical imperfections (like a side bumper being dead) that make it nearly impossible to play.
There is a bowling alley nearby that bills itself as a Pinball Museum (with 20 or so machines) but they're all quarter driven. I went once, dropped $15, got annoyed and never returned. My kids and I go to the other place every other month or so.
[0] Except for one machine -- they have this giant thing that uses a pool cue as a ball -- it's a Sega game ... Mammoth or something, and apparently very rare