On the one hand, when you use your card instead of cash to buy that coffee, there's absolutely a fee and it's absolutely bigger than the USD.04 I saw posted in

On the one hand, when you use your card instead of cash to buy that coffee, there's absolutely a fee and it's absolutely bigger than the USD.04 I saw posted in another bitcoin thread today as now being typical for confirmed transactions. On the other hand, for bitcoin to keep working we have to keep burning fossil fuels, and total transaction fees plus total mining rewards have to pay for that. At USD400/BTC, rewards are worth USD1.44 million per day. As rewards drop to zero over time, the transaction fees must rise to keep miners interested. Based on 600,000 transactions per day in 1MB-bitcoin, that's a $2.40 rise per transaction by time block rewards drop to zero in order to keep miners interested. Ouch.