Firstly, bitcoin is better than ordinary bills-it's safety from rubbing / stealing, as they were stored in an online wallet and will remain there. It is also convenient to buy something in European and Asian countries.
"Bitcoin is better than currency in that you don't have to be physically in the same place and, of course, for large transactions, currency can get pretty inconvenient."
Besides that of course with bitcoin then it automatically invests, the always rising price becomes an important consideration for everyone to put money on bitcoin rather than cash.