the funny thing, to me anyway, is that Talkbass is a huge forum with a lot of members. there's a sticky at the top of the main bass forum mentioning the G&L forum, there's said G&L forum, and there's G&L advertisements here on Talkbass. if i was making basses, i couldn't ask for more visibility.
yet no one knows them, sees them or plays them.
which goes back to the original question. why?
I see alot of folks playing MM basses and alot of kids coveting them.
I also hear alot of folks in clubs that just can't handle them....they can't EQ them to save their lives and I've swapped more stories with folks in studios that just about forcibly removed the MM from the bass players hands and made them play a P-Bass for their tracks because despite their worship of the instrument, they just didn't have the chops to sound good.
Popularity isn't always an endorsement of quality. PRS was a minor blip until the late 90's. It was then that they did two things; they ramped up production and actively sought out new and emerging artists for their roster. If you were a nu-metal band that got signed around 2000 then the odds are that a PRS or two was going to show up at your door for consideration.
They're fine instruments, but their proliferation is the direct result of their actions to get kids actively buying them.
I'm reluctant to crow about G&L. I'm a huge fan and I believe they make fine isntruments that are woefully under-valued. And personally, that's fine with me. I have three on the wall next to me and the odds are that I'll probably own more before too long.
For me the P and the J and the MM are thier own distinctive sounds. The G&L gets close, but it never nails it down. However, what it does to my ears is get that sound plus what I would want past that. The tonal flexibility, versatility and more of what I find I want out of a bass makes them a great pick for me.
It'd be blasphemy for me to slight others that got the job done with other tools. But I have found the G&L's are great for what I do and what I need them to do.
If no one else is buying them then fine by me! Stick with what works for you!