The "work" is growing the food.
In that case, I assume you'll have no problem paying the peasants for it?
As it is, the banker does the work and no one gets anything.
Huh?
If you're saying the work is growing the food, then the banker does none of it.
Otherwise, the banker does the trading and gets the profit from the trades he makes.
When the banker buys the food where does that money go? When he sells the food to someone else, who's giving the banker his money back? Am I crazy in thinking something is missing here?
If the banker buys food from an order set up by Lord Foodgrower, then Lord Foodgrower gets the money.
If the banker sets up a sell order and Lord Citymonger buys it, Lord Citymonger pays the bonds that the banker gets.
If the banker sets up a sell order and then buys it himself, no money ever changes hands.