I think G&L have always been a bit obscure and niche, possibly from lack of big-name players as you suggest, and less marketing than the big names. I believe they were difficult to get hold of in the UK for a while with distributor problems. It will be intersesting to see how they fare now with being exclusively sold by Andertons (and 2 other shops I think).
There's always comments and views about them being 'the authentic/true (Leo)Fenders' versus 'not a proper Fender(Musical Inst Corp)'. I think there is plenty of room for both to exist alongside each other. The other thing that seems to put people off is the teat on the headstock; it's not something that I really notice but each to their own (not all of the Leo-era instruments had this actually).
The 3-bolt tilt neck may still be seen by some as a point against them, this is from association with Fender's poor implementation of this in the 70's - it was actually Fender's poor workmanship and construction that was the problem, not the 3-bolt neck per se. G&L's used 3-bolts until 1996 with no problem, only changing because of the hangover from the poor 70's Fenders. Look at the classic model that @Jadenacre has advertised, 30+ years old, still great.
For those who do take to them, they are great instruments and very good value. I have 2 from Leo's era, a 1987 ASAT and an 1987 SC-3 (marketed at the time as a student or beginner guitar, it has a beautiful ebony fretboard - imagine that now). I also have a 92 Legacy, this still has a lot of the features from the Leo era but over the years, BBE (the new owners) standardised the production and removed some of the little touches and quirks, although making a consistent and still very good product. e.g. the bass that @bloke_zero is selling will have a hand-shaped neck which is a nice feature, the necks became all machine made from about 2005.
All this plus a slow market, as @White Cloud said, can make them a hard sell. The other side of this is that there can be some good bargains.
That went on a bit...apologies for the ramble, you can probably tell that I'm a G&L fan.