Sometimes keeping the peace is the opposite of helpful. Sometimes correction is needed, sometimes tables need overturned. I used to think that it was important to avoid conflict at all costs, and that shutting down a disagreement before it turned into a fight was my Christian duty. But sometimes, change is a good thing, and sometimes change requires someone who is willing to argue. Someone who is willing to upset the "peace".
Peace is not, after all, the ultimate goal. Complacency creeps in when things are too peaceful. People become unwilling to stand against things that are clearly not ok just to preserve their quiet, comfortable little bubble.
The goal is to become more and more like Christ, and I can't speak for anyone else, but for me that means a lot of growth, and a lot of change. If I am more concerned with surrounding myself with peace and comfort, then I am also shutting out opportunities to grow, to learn, and to exercise my faith. Conflict is uncomfortable. But without it, what would I have learned?
I don't mean to say that peace is without merit...but I can more easily see the beauty in the quiet that follows a storm than I can in a month of consistently quiet days.