TL;DR: economists are still stuck in the idea of the market as a perfect force for reaching optimal outcomes. They're ignoring the simple fact that businesses are putting prices up purely to increase profits. And that they can do this because the economic ideal of perfect competition (where many small firms compete with near-identical products) does not exist. We have a small number of very powerful businesses—oligopolies—in nearly every market for consumer-facing goods.
Who's going to fund the new economics building at the University, the working class or some billionaire? Better make sure you don't have any Marxists on staff.