Disable automatic contact creation for Conversations

It is next to impossible to segment our contacts to send targeted content when our contact data is so incomplete due to contacts being auto-created. When we add contacts to our system, there are a number of required properties (eg. job function, region, industry, etc.), auto-created contacts do not have any of this information. The example above of how Salesforce does it is exactly what I envioned to be a great solution for this issue - a pop- up notifies us in the email exension whether or not the contact is in the CRM, then we have the choice on how to proceed.