Why is the Watchtower so afraid for anyone to miss a meeting? Time control is part of cult indoctrination, it keeps people constantly busy trying to please a never satisfied organization, so they do not stop to question anything.
Not only is it about 'busywork', but it's also about maintaining 'group think'. The 'information' at JW meetings is extremely repetetive in nature ("end is coming" "do more" "world is evil" "jehovah is magical"). So much so that even the most mundane variation, such as a 'tract campaign', is considered a 'special announcement'. The somewhat delusional teachings need to be continually reinforced, because otherwise the rational part of the mind begins to see the ridiculous teachings for that they are.