I lthink your point has some validity, jd.
I don't agree with your view on the motives. I think some magicians enjoy their hobby (or career) so much that they think everyone should love it as much as they do, and are therefore keen to encourage others to join in.
There is a bit of a difference between magic and many other performance arts; it is possible to do tricks with little or no technical ability. You can buy gimmicked props, or perform self-workers. Almost anybody can do a magic trick. What some people lack is the ability to perform magic well. An adequate singer can sound good with Auto-Tune. An adequate magician with great tricks is still just an adequate magician.
User24 - I think you are missing the point. The question is not whether
you could learn to play the piano, or to paint, but whether someone who had no aptitude in those areas
should even try to learn.
Grimshaw - You might just be a naturally talented person, like me.

However, if you ever heard my father sing, you would understand that some skills simply cannot be acquired by some people. Ever seen that episode of
Friends where Monica's millionaire boyfriend is determined that he's going to win the UFC? By the way, being a Dad takes no skill at all. Being a good Dad takes loads.
DaveM - Have you ever seen the "hopeless" auditions for talent show programmes? Do you think their relatives were doing them a favour in telling them they were good, or would a reality check have been much better?
Having said that, I really can't see why we can't just let people get on and enjoy magic. If they want to spend lots of money and time on a hobby they don't do well, but they have fun with it, let them. It's not like they are having a crack at neurosurgery when they don't know what they are doing.