If you use stop losses it will be a lot more than that. You also aren't taking into account the biggest one which is the price of borrowing. You don't get that huge contract for nothing. The interest is pretty substantial over time. If you are going to trade ES and be profitable over a long-run I'd think you would have to have a spectacular swing trading system that aims for significant profits, not just grabbing 500-1000 here and there.
you can trade and make the market pay for you commissions and any slippage by trading counter trend. make the market come to you. always price into a market at better, than the actual trade entry price. those small ticks add up to big numbers.
It's probably not the reason. A mechanical engine can do far more than one human, it can work hard, has lots of power plus staying power. A retail trader at home needs an engine. Building an engine at home for a retail guy is not easy, just like building a motor in your home workshop is not easy. A retail trader at home trading is a bit like someone trying to create a vege garden with just a shovel. It's all manual and back breaking and slow.
Well it is hard in a way because it actually demands a lot of time in analysis and checking the upcoming events before trading in any element.
Unless you can count cards. In the market, even if you can count cards, unlike the house, they cannot ban you from trading.