Some people cannot just take a compliment when people say "you take great pictures, you should be a pro!" and not let it go to their heads. People say that to me at times and I just say "thank you" and realize that I am NOWHERE near as good as "the pros". Most people will compliment just about anything. Its just like anything else, you can be a scratch golfer but that doesnt mean you could make it on the pro tour. Those guys are on a completely different level than great amateurs.
Yeah but there's also people making money off photography, meeting the strict definition of pro, who aren't as good as some dedicated, talented, amateurs. Its not a hard line between pro=great and amateur=mediocre.