There is no email address for customer complaints. I think there is some form of twitter or facebook or what such available for publicizing grievances but I do not have the specifics of it. Try searching these forums for it.
Adobe does not hide that subscriptions automatically renew, they do not seek your approval to do so. If you read the EULA you will see the detail of that, but even without reading that it is explained in their pre-sales literature. It is up to you to keep track of your subscription and end it when you intend.
All right, I'll bite - how do O end my subscription if I can't email? I don't intend to end my subscription, I'm asking because I want to email my support query; I'm not interested in hanging on the phone or computer to find out WHY CC NO LONGER OFFERS A CS6 UPDATE.
CS6 is over 4 years old and is no longer updated... if you think your CS6 needs an update, start here and select product, read to see if you need to install updates in number order, or if the updates are cumulative for the individual product http://www.adobe.com/downloads/updates/
If what you are asking about is using the Cloud to install CS6...