[human20190310]

The good news is that the broker isn't screwing them.

The bad news is that the reason for that is because the broker doesn't have to screw them; they're uninformed noise traders buying and selling in basically equal measure. The traders buy at $1.001 and sell at $0.999 as much as they want until they're blinded out by the spread, which the broker keeps.

The "savings" being passed along is just a reduction in the portion of the spread that the broker would normally use to protect itself against informed traders.