Although alot of people use it for the bad reasons, but the percentage of people using it the right purpose is more,and yes we do need bitcoin, since it has become part of our daily life, I really can't imagine the world without bitcoin now ,bitcoin has made life so easy for most of us, especially for people in the third tier countries where doing any transaction outside the country is pretty hard, it takes some days or maybe a week for one to be able to send money to anyone outside their country, but with bitcoin transactions have been made easy without the middle man (the bank).