Hi. Great question. The $ money comes from market makers who profit from the bid/ask spread. If they pay you the bid price, they likely made money selling it at the ask ether before or after  they paid you, they are constantly in and out trades all  day long. Also,some day traders or swing traders pick  up cheap oout of the money options just to profit on scalp treades  or intraday moves. That's why it's important to focus on high quality grlwth  stocks that have a very liquid and active opttions market.