I don’t see how it’s a benefit to capitalism or companies or, well, anyone, really, to allow people to make thousands of trades a day for minute profits on each.
My gut feeling is that the stock market would not suffer, and less resources would be wasted, if trades and updates to stock prices were limited to, say, one batch per hour.
There are probably reasons the system is the way it is though.
The investment bank already does that and calls it commission. It’s basically how the Wolf of Wall Street’s main character got started: commission on penny stocks.