Money is nothing more then something we have given value to and is small and easy to carry and use everywhere. You can trade money for anything you want since it has value. Bitcoin is the same since it also has value but usually Bitcoin is seem more as an asset like stocks. That's why the exchanges are basically digital stock markets.
Correct sir, in real money all people can able to used it even poor people they can while in bitcoin limited people can used it because not all people can afford gadgets to access bitcoin.
For now bitcoin is much better to invest than using real money because the value of bitcoin now is very high and it was continuous increasing, more investor now start to add some amount of money as bitcoin investment.