In my neighborhood there is a supermarket which is owned by a non-religious Jew. He keeps it open over Pesach and sells (and presumably buys) chometz. The community does not purchase chometz items from that store for 2 weeks afterwards, which is time enough for all the chometz items which had been owned over Pesach to cycle through the store and be replenished.
My question is: is there any prohibition attached to the money made through the selling of chometz over Pesach? Meaning, for example, if the store owner sold a loaf of bread on Pesach and now wants to use that exact same physical money from that sale to buy something from is there any prohibition involved?