Because apparently no one is willing to buy shares at a higher price. If sellers want .0002 or higher and buyers want .0002 or lower, the MMs won't make money on such transactions. So, they fill sell orders at or near the bid and buy orders at or near the ask then pocket the difference. BTW, this is how the market works here. Since the stock is quoted unsolicited on the pinks, MMs aren't allowed to make a market on their own in this one.
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"We simply attempt to be fearful when others are greedy and to be greedy only when others are fearful."
-- Warren Buffett