Citadel and friends pay to trade with you because they think you’re dumb and they can make money off you. They’re giving you or your broker a better deal because they think they’re smarter than you. That’s all it is. They’d rather trade with you than with the median person on the market. Because they think you’re dumb.
You’re welcome to be insulted by that. It’s an insulting thing. But it’s not some grand conspiracy.