Few people need much of a front end for the actual PCBs they own I only have 20ish, but I have quite a few ports and compilations for numerous systems so I justify it in my head, mostly because the PCBs are out of reach for me or just not available.

Sadly, I also have MK9 on 360 and the collectors edition controller.
Again, not a pissing match, I know there are guys on this forums that have more cabs than I have cabs and PCBs and CRTs combined!
Nowhere near enough.
To cover all the games you're pirating? While I do not doubt your ability to program, I do doubt your sincerity that you don't emulate games you don't own if you have a "big book-o-games" you're getting bounded. SO your either lying about what you emulate or you're lying abou thte amount of storage space you have in your house.
Vigo, I'm less private than her, I have 7 machines (Killer Instinct, Mortal Kombat II, MsPacMan, Galaga, Pole Position, Generic Dynamo that was a factory SF3). PCBs uhhh going from memory ........ Street Fighter 2:WW, Kung Fu, BreakThru, NBA Jam, NBA Jam TE (all revisions), MK1 (rev 5.0), MKII (all revisions), Umk3 (1.0, 1.1, and Juggernaut hack), WWF Wrestlemania, Killer Instinct, Killer Instinct 2, Ms Pacman (with and without speed hack), Pacman (with and without speed hack), Galaga, 60 in 1, some horseshoes game that I use as a JAMMA tester, a broken 15 in 1. Im sure there are more but Im drawing a blank, one of the caveats of getting old.