It's especially hard because Aunt Harriet's order almost certainly won't actually make it into the open market. Her broker will very likely "internalize" it (tr

It's especially hard because Aunt Harriet's order almost certainly won't actually make it into the open market. Her broker will very likely "internalize" it (trade against it themselves), or sell it to someone else who will (e.g. Citadel will happily buy their flow.. they bought Ameritrade's last I checked). That very well may be the future of these funds - compete for the customer or pay for order flow like in US Equity Options rather than compete in the open markets. All the orders that can be traded against with any of the typical profitable strategies (most strategies at these places are fairly well known and similar).. won't even make it to the real market. Doing it this way avoids the risks in the open market, notably adverse selection and the need to over-represent your interest in multiple places to increase your execution quality.