Margins go up when firms have pricing power. This happens when demand outstrips supply. The system is set up to raise prices to allocate that supply to whoever

Margins go up when firms have pricing power. This happens when demand outstrips supply. The system is set up to raise prices to allocate that supply to whoever values it most. You can argue for different systems of allocation, but right now we use capitalism, and it’s working as intended. We can also argue about why demand is outstripping supply. Are monopolies keeping out competitors and artificially limiting supply? In some industries probably. But we did dump a ton of money via fiscal stimulus into a system that was already stretched thin due to supply chain disruptions. That seems like the most likely explanation for the broad inflation we’re experiencing, though consolidation has likely exacerbated the problem.