The newsletter manager has other options to give you more control of your campaigns -- eNewsletter Preferences and Manually Unsubscribe Email Addresses.

Preferences
The eNewsletter Preference button brings you to the settings page for your campaigns. These are global settings that will be applied to all of your campaigns, unless you specify differently when you create a new campaign. The options are the same as the step-by-step options that appear when you create a campaign. To review these options further, see Email Newsletter Manager. 

Manually Unsubscribe Email Addresses
This link, at the bottom of the manager, allows you to enter the email addresses of people who wish to opt-out of future campaigns.