I think it is not hard to use bitcoin as a regular currency. Because bitcoin is an electronic money and i know that someday it will be known and will be use by many. And bitcoin has no difference with the atm that we have today. Bitcoin is helpful and bitcoin is safe so it can be a regular money currency.
I think you haven't research enough about BTC. It has already been known world wide and it has been used by many people.
BTC has a big difference in ATMs. As you have said BTC is a cryptocurrency, and ATM is an access key to what you have saved Fiat money in you banks.
BTC has so much difference in ATM.