Actually the number of complaints was miniscule compared to the number of Gmail users and most of the complaints came from people who thought the suggested names were actually being added by the feature which was not correct. Google are not likely to disable it since it was available as a Lab feature for months before it was migrated into the production system - therefore Google must consider it useful.
Many users find it useful as it saves having to build Contact Groups for groups of friends that you send group messages to regularly. The feature does nothing unless you click on the links. TCs rarely offer third party solutions because we can't verify their safety or reliability - all third party solutions are likely to break at any time as a result of changes made to the Gmail code. When we say something can't be done, we mean it can't be done with standard Gmail options.