[jonathanjaeger]

Maybe in part, but I think for the majority of people thinking positively about a situation results in a nodding of the head and moving on. Most don't find it interesting or adding to the conversation to just write, "I agree because of what you said or because of X, Y, and Z."

If you disagree, however, there is an emotional tendency to want to argue or lash out(especially under the guise of partial or full anonymity). Arguing makes for a more interesting read or prevents the 'yes' mentality.