North Korea (you referred to in the extension of the question) is a dictatorship, not quite as benevolent as socialism. A necrocracy in the words of Christopher Hitchens, as the dead grandfather is still the official leader.
But to your question, non-socialists tear down the stale merit of socialism and thus is by the group that promulgates socialism heavily disdained for self-preservation purposes. Socialists are resistant to the kind of change that would challenge and reshuffle their pre-established status and rank.
Mind you; socialism is a symptom, not a system. A symptom of colluding groupthink, omnipresent in many systems, not excluding the financial systems of many democracies. And the same intolerance to those aiming to disrupt financial systems is present there too.