[derefr]

To stretch the analogy, the equivalent of an HFT firm in English folklore would probably be a toll-road operator; or a city-state customs officer accepting lesser private bribes in place of levying greater official tariffs on imported goods.

Robin Hood, by stealing from the rich and giving to the poor (in a period with commodity currency with no monetary policy), would be encouraging deal-flow (as the rich traders stolen from need to send the same goods again to fulfill their contracts; and the poor now have money to spend to purchase exotic goods, requiring more be imported by traders), in turn increasing travel on the toll-road/through the customs office, in turn making the toll-road operator/customs officer money. It would make perfect sense for the mythical Robin Hood to, in fact, be a toll-road operator/customs officer — or at least to be in cahoots with them.

(In fact, come to think of it, he wouldn't even need to steal from the rich, per se. He could just destroy trade caravans, and collect a cut of the revenue from the toll-booth operators; or destroy goods already imported but not yet sold, and collect a cut from the customs office; and then distribute said cut to the poor. The same virtuous(?) cycle would occur.)