That's not the proper understanding of human nature. Game or real life, it doesn't matter. We all have emotions and negative emotions tend to overflow more than positive ones in most cases.
Though I haven't followed this game but odds are really high that most if not all will tend to neg those users out first whom they don't like much
With gradual progression of the game, voting will happen on the basis of degree of personal likeness and it's natural.
And, not everyone has habit of taking games just as a game like you two are saying