There are a lot of reason for which you can you choose bitcoin the major reason is that bitcoin is cryptocurrency and you will use them anywhere in the world so it means you can change it to any currency which you can used this money for every work.
Bitcoin is also available on most of the exchanges. When you deal with altcoins, sometimes it becomes a problem to exchange the coins for fiat or other alts.
you are right, bicoin is easier to exchange with fiat currency, if and choose altcoin then you must exchange it with bitcoin before exchange it with fiat, bitcoin also safer to hold for long period of time