Often people who aren't very intelligent see people who are intelligent as the 'wise guy' or other more colorful terms you use.
A person who is truly intelligent, knows they do not know anything. I might very well be wrong on every account and I realize this. What I think 'I know' is all created by my past experiences and thoughts.
Talking bad about other people and spreading vicious rumors though, whether we know them or not is something I'll not normally participate it, except when being obnoxious. :)
It's hard to be humble... when surrounded by snakes.