Problem? Well, a minor inconvenience. For me the difference is that I specifically need to reserve cash to pay taxis in Germany, not for any other purpose. Nor

Problem? Well, a minor inconvenience. For me the difference is that I specifically need to reserve cash to pay taxis in Germany, not for any other purpose. Normally, I don't carry cash with me, except for a few coins for a bus ticket or a vending machine or a quick lunch. I don't even carry a wallet; I have a phone case which has pockets for driving license or ID card, and bank/credit card. Above, I said credit card, but I actually use it as a direct debit card. I pay may lunch and groceries with it, and gas and parking, and whatever. If I make a one-day business trip to Stockholm, I don't need to make any special preparations: I can pay everything with the same debit/credit card, and I don't need to change any currency even though Sweden does not use euros. If I make a one-day business trip to Berlin, I do need to prepare with currency to pay the taxi there. If Uber brings pressure for taxis to accept debit/credit cards, that's good.