First of all bitcoin is anonymous and cash not, when you want to cash out your bitcoin you have to pay some fee to do that, that's not happening with real money, and also you can use your bitcoin where you are but you'll have exchange your money with the currency there is where you are.
The difference between bitcoin and real money is simply, bitcoin was created to take the place of fiat and to adopt to the current way of life and the different needs of people who by the time changed their thoughts and their habits, having internet or online shopping was something that we didnt know existed before and now it is a part of our daily lives, and the digital world that we are going toward needs to have a different way for us to pay for things and from that idea came the bitcoin.
But I believe that one day we will be having bitcoins with no differences from fiats. Yes, bitcoin will do all the actions our local fiat will be doing.
Maybe our got the thing right that it was created to replace fiat but it won't happen so soon it will take lot f time.