Cryptocurrencies give you a deflationary option. Don't like it? Don't use it.
I think cryptocurrencies are the future, and we will see more and more stores accepting them, and the conversions will happen automatically.
As a customer why would you make payment in a currency with high fees, poor ux, slow transactions and just enough anonymity to make it perfect for scammers?
As a payment processor why would you touch this currency with a barge-pole given the above problems?
Cryptocurrency isn’t the future of currency or payments, and bitcoin in particular is solving the wrong problems, badly.
Physical currency was always an instrument of states, and now they have better ones, which retailers, consumers, and states prefer (digital currencies, not cryptocurrencies). In many countries cash usage is down to 20%, it's expensive to produce and manage and not required any more.
If the gov't can maintain a bond rate below that of the inflation rate, it also acts as a small tax to help fund the gov't - which also isn't a bad thing.
Not that any of this matters at the moment, because the real limitation of cryptocurrencies is the tiny transaction throughput.