There's nothing wrong with selling proprietary software. What really irritates me are companies like Redis who pretend to be open-source and start whining when

There's nothing wrong with selling proprietary software. What really irritates me are companies like Redis who pretend to be open-source and start whining when other people (like Amazon) earn money from using their software. I believe open-source is about altruism. It's not a business model to gain users and thereafter trick them or forcing them to pay.