Remember that the Fullerton Deluxe basses are really just BTO basses Built To G&L's Order.
That's an excellent way of putting it. On some of the Fullerton Deluxe models, there is only one color and pickguard combo available. If I remember correctly (and the last time that happened was during the Carter administration), the only Fullerton Deluxe Kiloton this year was a metallic tangerine with a tort pickguard. It was unusual-looking, but kinda nice.
But there are more colors available for Tributes. It seems sort of obvious that G&L Fullerton just doesn't have their heart in producing basses to hang in stores. The BTO and Custom Shop seem to be their real passions, but the Fullerton Deluxe series might reach an economic range that BTO and Custom Shop can't and also serve as good advertisements for what G&L is capable of. Considering that I run into players all the time who still don't know what G&L is, that advertising seems important, unless they're as busy as they ever care to be.