Contrast this with the fixed-money supply of bitcoin:  If I put my house in the market for 1000 bitcoins, I'm reducing the bitcoin supply by 1000 bitcoins.  Bitcoins get scarcer and their value relative to goods (my house) increases.  The next person who mortgages an identical house for bitcoins will receive fewer bitcoins than I did.  We both put in the same amount of goods but we get different amounts of bitcoin, depending on who made the transaction first.  Does this seem a fair exchange system?