You are wrong. That would be totally illegal, and the SEC would close them down or fine them. They are BROKERS, sort of like cashiers in a store. The ONLY money they make is off the spread. Period.
All of this talk about Mm stock manipulation is ignorant traders that don't understand what an automated market even means. There are NO people involved in our trades, only computers. No tin hatted guys with their secret laptop trying to make beer money off penny stocks. Jesus, educate yourself.
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