Its my impression that a trader like you sells and buys from the MM's not necessarily trader to trader. The MM's have a stock of shares available to sell, especially after the sell off of last week.
MMs maintain the market. The diff is in or out of MMs inventory. Every buy matchs sell. If only seller/buyer no buyer/seller, MMs buy/sell. MMs trade their own acct too. This is an old question not dumb q...lol
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