Yeah. The whole discussion about people not being artists or being artists because of this and that is kind of like telling someone they don't have a job because they work at Wal-mart rather than being CEO at a Fortune 500 company. Sure, there are lots of differences between the two jobs, one can be considered better than the other, and one most likely takes a lot more time and effort to get and keep.. but they are still both jobs.
Telling a person who works at Wal-Mart "You work at wally world?? That's not a job!" would be extremely rude and degrading.. but for some reason people don't see it that way when they say it to an artist.
Most people i know involved in art have very little to do with photography. Not to say they don't, but it isn't their primary choice of a medium. Being a artist in photography is difficult. Not only are you attempting to circumvent the copying or record nature of the medium but the long term learning and skill level is high. You can spend many years learning photography. As i had a discussion with someone else a few weeks ago. The problem with learning the craft of photography (camera, lenses, gear talk, processing, basically gear and tech talk) is it is easily a creativity killer. The more you attempt to learn and get caught up in the technical, the more creativity is sucked out of you. Why some of the more knowledgeable photographers may be considered great craftsmen but zero for artists. Some of this stuff is the equivalent of trying to making learning calculus art. As you mentioned they are very different. And balancing the two sides of that coin is exceptionally difficult. I can't speak for others, but when i read through about a lens, pick up a book for a while, look at stats or lighting diagrams. It pretty much sucks the creative life right out of me. Why i still reduce myself down to a simple point and shoot sometimes and stop thinking. But to achieve great art in photography it takes the vision and the skill is my thoughts. That is a huge amount on ones plate to balance and digest. why it is such a difficult medium for artists, not to mention the nature of the medium itself (record) has to be surpassed also. There are other mediums that lend it much more easily for someone to explore their creativity and express themselves.