No, you don't have to make an individual relationship but you can if you want to and have to with Add2Exchange Standard.

The Best and easiest way is to use Add2exchange Enterprise edition

And use the Relationship Group Manager

Then you make a relationship template to the service account mailbox, making any folders you want there

then

Attach a new distribution group you made for this purpose and add the people you want the information to go to in the distribution list

Call it z_a2E_pub_contactsync or something like that so the name says what it does and then attach it.  Then close the Console and let it sync and it will make the rels for you and make the directories if needed

See this link:

http://guides.diditbetter.com/a2e-guide/relationship_group_manager.htm

Review the manual for both option

Hope this helps!