CRM - Address Entity - Access Privileges

In CRM how do you control the security permissions for the entity 'Address'.  When you go into Settings>Security roles, Address is not a record that you can alter permissions for.  Why not?  I have four user groups and of these three have read only access to Acocunts/Contacts and I want this permission to extend to 'More Addresses'.  However at the moment these read only users have create, read, write and delete access to Address.   How can I alter this so they only have read only access??