generally, the economics of valuation are different. the price of a stock isn't necessarily tied directly to the supply of anything. a company can grow and issue and grow and issue and grow and issue, etc. etc. a futures contract has an opposite on every trade and is tied directly to the supply and demand of a commodity or underlying.
Have you heard the expression, "A smart man learns from his mistakes. A wise man learns from the mistakes of others." I am both.
I don't scalp them, since I no longer have the energy for that game.... however, there are a large number of professional traders making a great deal of money scalping for ticks...
My guess is that's a myth. There may be a few, but a "large" number? And whatever there are, they probably have a front-running edge of some sort.
Well, that's a good enough proof for me. I hope it's good enough for all the other folk who might have tried this dead end.