how does putting your house on the market reduce the bitcoin supply? they don't disappear, they just change hands.
It reduces the bitcoin supply for everyone else.
Conventional money is not meant to be a precious commodity whose value changes according to supply and demand. It has a supply that grows with demand and matches the overall economy. Creating money to match the demand of the economy is a good thing because it maintains the buying power of money relatively constant (slowly diminishing, on purpose).