Why is Poly1305, which is based on AES, faster than AES?
Poly1305 is not based on AES, it was used together with AES in Bernstein's first description http://cr.yp.to/mac/poly1305-20050329.pdf. For pseudocode of the Poly1305 algorithm see e.g. https://tools.ietf.org/html/rfc7539#section-2.5.1.

GHASH is the 'hash function' in AES/GCM. 

So if Poly1305 is faster than GHASH on some hardware this is no contradiction. And note that the peek values on your linked site are comparable: Poly1305 1730.92MB/s, GHASH 1740.96 MB/s.