Some good reasons why you use bitcoin.
1. It is fast. Transactions are instantaneous and confirmation times are usually done withing 10 minutes.
2. It is cheap to transfer any amount of money anywhere. Fees are insignificant at this point.
3. Your bitcoin are your alone, they can't be blocked by bank, IRS or any institutions.
4. There are no charge backs.
I think many good reason for this one. First, bitcoin was giving opportunity to many people to earn easy income and good income. Many people are hanging on this and they satisfies about what bitcoin can do.