Mrs Lime is just misunderstood

I met Mrs Lime in person. He was polite, unassuming, softly spoken, and totally non-confrontational. I had a problem with my computer and he let his dinner go cold while he spent two hours helping me to sort it. During that time, he spoke very little, when he did he didn't make eye contact and his voice was just loud enough to be audible.
I have a habit, developed over years people watching and dealing with total strangers, of catagorising people quickly, sometimes I'm wrong, but not often.
I had Mrs Lime down as one of life's good guys. Shy and retiring, helpful and accommodating. Obviously blessed with a massive intellect, he seemed secure in the knowledge that he was mentally superior to most of the people he came into contact with, and happy to use his abilities to assist those less capable without ever coming across as being arrogant or condescending.
Then I saw the version of Mrs Lime that you all know, the online version. Rude, caustic, outspoken, troublesome and vulgar. He seems to delight in upsetting people. Bulling them into submission by beating them over the head with his intelligence and his vocabulary.
I know it shouldn't really matter, and perhaps I've spoken out of turn here, I'm just as guilty of rising to his bait as everyone else. Somehow though, the whole thing saddens me.