One "problem" I see in this thread is that some people seem to want to equate "Working Photographer" with "Artist" and the two terms are not interchangeable.
I know several working pros who support their passion (Aviation, Fine Art Nudes, Fine Art Landscapes) by taking gigs shooting the most mundane of projects. E-sessions, Weddings, Seniors, Products, String for the AP, HS Sports, Event + On-Site Sales.
The common thread with all of them however is that they have the ability to deliver on spec, on time, every time. Not just when they feel like it or when the planets align properly but through rain, wind, snow, darkness, gear failures (they've invested serious cash to have backups for backups .. many amateurs don't), flaky models, flaky clients, flaky MUAs, double booked locations and on and on and on.
The true test of a "Pro" isn't what you can produce when everything goes right. It's what you can still produce when everything goes wrong!