Not sure how that works between MM's?

IMO, even if they paid fees etc, they benefit in the long run taking the price down. There are people who bought lets say for example only, just a while back at .0033, see it drop from .0046 to .0042 today, and they sell.

This is one way the MM's make money by causing panic selling, then raise the ask another day.

A simplified explaination, not 100% accurate, but you get the idea.

GRIM is more versed at this....