People stockpiling only "weap9n"s aren't going to last near as long as people stockpiling only food.
In real life melee weapons are readily available and far more overpowered that you'd think, but what matters more is that robbery is risky. Winning most of the time isn't enough; you'd need to win all of the time.
It depends on if the people with weapons can find the people with food. With no rule of law, everything is on the table. Warlords still exist in many parts of the world today