bitcoin also future currency. some times we have no internet facility and we have spend less money also, in this cases cash is better.bitcoin price also very high so we cant use this for small shopping's.all shops may not accept the bitcoins.
Also it is not necessary to use the bitcoin mustily.
Bitcoin is a crypto currency it is comfort to use on online and fiat is better to use in open world.
But i disagree in these points that cash is better than bitcoin and bitcoin is better than cash.
Cash is good for everything and bitcoin is good for online working.