I don't purport to have any special insight or discernment into Bob's psyche, but I do feel that I share two traits in common. Those two would
NOT be
talent or intellect, but a painful shyness and insecurity. The insecurity obviously does not lie in his gift, he is all kinds of bold when it comes to being true to his art. That comes after he has laid his bare inner-self open for people to receive or to reject.
When you are painfully shy, it really does not matter how many accolades or awards you receive. It does nothing to change the reality of the person that you are. You can try all day long to be something different, but you can not. So, when this keyboard player (or fan, or reporter, or other artist, etc...) walks by,
first, you do not imagine that they even want to speak with you. You do not see yourself any differently than the regular person that you are. Not the messiah, extraordinarily gifted songwriter, rock star, or whatever else someone's perception of you may be. So it would be presumptuous of you to assume they want to meet you. Secondly, even if they do want to meet you, you do not know what to say. Conversation is as difficult as anything you can imagine. IT. IS. PAINFUL. It is frustrating. It can be humiliating. They way he communicates is his art. That is the expression of himself.
He is able to overcome shyness to perform because of several factors, probably. This is where he shines. He doesn't have to interact, except intuitively, and this is the place where he feels the most secure. Also, I think this could have been why he wanted a band and why he had so many others tour with him during the RTR. He is an artist and he has no choice but to do what he does, but there is a sense of security in having people around you and relieve a bit of the pressure of glaring, critical eyes. He probably was able to perform solo when he was so young, simply by sheer force of will, but it caught up with him.
All I am saying is, he doesn't hate his fans, or people in other bands, or even the media. This of course is how I perceive him to be. I may be way off base, but I think I am able to recognize that he is very shy because it is my reality. Talking on a message board is much easier than real life
Oh, and one more thing. People that do not have these characteristics do not comprehend this. They believe you are snotty, stuck up, rude, or something along those lines.