For a cup of coffee you probably don't need to wait a full day to be certain the transaction has gone through. Blocks are mined on average every 10 minutes and

For a cup of coffee you probably don't need to wait a full day to be certain the transaction has gone through. Blocks are mined on average every 10 minutes and pending transactions are broadcast immediately and (assuming a large enough fee is paid) will be included in the next block. For a $3 purchase, you probably don't even need to wait for it to be included in the blockchain (although to protect against double spend you do). But the poker guy is right, bitcoin is not really appropriate for replacing credit cards for small purchases at the minute for several reasons: 1) You must wait between 1-20 minutes to get your transaction included in the next block. 2) You must pay a fee that could be 100% of the total transaction or more (for small purchases). 3) You must pay capital gains tax on your purchase (possibly at the short term capital gains rate even), which complicates your tax reporting. Issue 1 and 2 may be solved with technological solutions soon, if the lighting network (distributed settlement layer on top of bitcoin) is successful.