nobody needs a hotrod car, but they are a lot of fun....I don't believe anyone needs an AR
but I do believe in people's rights to own one should they desire one.
I don't need an AR, but I don't want to miss out on owning a hi-cap semi-auto long-gun.
The AR15 is not your only option of a semiauto rifle. It is the most popular, but currently way too overpriced.
Unless you really want an AR-type rifle, Look also at Mini14, SKS, and AK's.
Unless you feel a need to own one save your money and get something you will actually shoot regularly that is easy to maintain.