How to create both anonymity privacy and still achieve address reputation for merchants
Stealth Address is the answer.

Adapted from CryptoNote technology by Peter Todd (I think), Stealth Address basically is a form of Diffie-Hellman key exchange that allows sender to create a one-time key pair that only receiver can derive the private key. Thus Stealth Address allows merchant to public their well-known address while prevent any payments to be link to that address.