Well that is a very good question. You need to used a bitcoin to get and earn more a money using of bitcoin. because Bitcoin is just like a money. You can use bitcoin as payment like a money. Or you can sell a bitcoin or exchange a money. That's why I'm using a bitcoin untiL now. To earn a money.
And the second is it just easily to used Bitcoin because your the the only a boss. And the transaction is faster.  That's why we need to use bitcoin.