I used to buy a coffee from time to time with bitcoin.
But I can't use bitcoin buying a coffee now, because the fee is so high, if I keep 0.0001 fee like before, it would take days for the transaction to get confirmed, I've got a transaction which took 11 days to get the 1st confirmation last month.
It's not cost-effective any more to buy (I mean both online and buying face to face) thing via bitcoin. And this is why I quit buy coffee with bitcoin.
Well maybe you need to raise the fee. Thats the point of the fee. The higher it is the less long it takes to complete the transaction and get the confirmations.
But, buying coffee with Bitcoin isnt really practical anyway. Unless you make a living with Bitcoin just buy your beverage with your local fiat currency. People are always romanticizing about buying everything in bitcoin but it is actually more convenient for you to just use your government backed currency.