Hi Matt,
This is an expected behavior while using A4T, If a user is a part of an activity using A4T then the value of the activity will be associated with the visitor till the expiration of the eVar(90 days). As a result the activity would continue to get page views, visits and so forth even after it has been deactivated fro some time. Having said that post the activity has been deactivated the user should not see content from the activity and more relevant metric to check this would be impressions.
Hope that helps.
Thanks
Raag