The notion hald by guitar players that their musical universe is somehow unique and complete never ceases to amaze me.
Frankly, I would have guessed that more than 80% of the buyers of almost any musical insturments or gear - including modelers - are non-gigging ("bedroom") players. My experience since early childhood and common-sense observations have led me to that conclusion.
Consider the kids who begin taking music lessons in elementary school or earlier. Many, if not most, of them have instruments and associated gear that their parents purchased for them. Over time, it's become less common - and yuugely more expensive - for parents to buy nice pianos, hence the proliferation of cheap-to-modestly-priced electronic keyboards. When I first took music lessons many years ago, widespread acceptance of electric guitar as a "legit" instrument had not yet occurred, and modelers didn't exist. Hell, fuzztones didn't exist. As time went on, all that changed, and it was then not uncommon for parents to buy an electric guitar and a small amp for their child. I'd guess that a substantial portion of the market for electric guitars and associated gear is parents buying stuff for their kids. Extrapolate that to high school kids playing in bands, including school bands and garage bands (do kids still do that?), with some of them gradually coming by their own money and spending some portion of it on gear, and you're adding another substantial portion of the market. Finally, you have fully grown men buying gear for their own purposes, in many cases for bragging rights, in some cases to actually play. Compared to those three submarkets, my money says the total market share due to working musicians is less than the implied 20%. That includes any gear, not just modelers.