I wish I could paint as well as this
... said Rembrandt to Goya.
I'd settle for your 'lack of talent' any day... I may as well be using a white-washing brush in comparison to some of you LPL guys.
Like any 'professional' the guy obviously has to consider his time, which is not the same for the 'beer and fag money' painter. You can do your job for the love of it sure, but it doesn't pay the rent. In effect the hobby painter keeps the price down, in the same way as 'hobby writers' (most of whom write for free, even when the publication they write for is 'sold') keep the already appalling word rate down for pro writers.
Oddly figures can command a price other aspects of the hobby (terrain, buildings and even the cases to carry your 'works of art') cannot. A guy will spend a small fortune on figures, spend hours painting them and then carries them around in a €2 file box.
You can whinge about dentists, plumbers and whatever 'over-charging' too, but they have previously expended time and money getting the skills, qualifications and indeed premises and tools for the job... their cost includes that... maybe there are 'hobby' dentists around, but would you be willing to try them out? Obviously there are 'hobby builders' however...
As in all things however, the market sets the price. We may think the price is extortionate, but clearly his customers do not. Only by people not paying the price would it be reduced. Many of us baulk at GW prices, yet they still carry on (just about by the sounds of it admittedly) as they have a customer base who will pay.