Can I Stop iCloud from Syncing My Profile Contact Card?

We have three different mac's each with three different profiles. Due to the nature of our small business, we each need access to the same contacts and calendar.

iCloud is perfect for that. All of the accounts sync to the same iCloud account for this.

Unfortunately iCloud is syncing contact cards to our profiles. So if one person changes their contact card, it changes it for everyone. That means that we keep seeing each others profile pictures on our accounts when we log in. It also means that Bonjour chat doesn't work right.

I've tried turning of document and data sync in iCloud. I've also tried going into users and accounts and making sure each account was assigned to a seperate Apple ID. None of this has worked.

Suggestions?