ADDR_NAME issues after upgrade from 7.8 SEA to 8.1 SIA

We are upgrading from 7.8 SEA to 8.1 SIA.  With that, we are moving from 1:M to M:M for addresses on accounts.  We have discovered we have a significant number of addresses that will be duplicates.  The business users have looked at the addresses and without using postal code (zip code) in the addr_name they feel a bit challenged.  Using addr_line_1, addr_lilne_2, city, state for the addr_name doesn't workk too well.  Has anyone else come across this? Did you incorporate zipcode in addr_name? If so how did you do that?  Or did you make a different change to addr_name?  If so what