I don't know if it was an intended design to allow the provision house (and barracks) to keep working in the past, but it was extremely useful. I can see the value in freezing other buildings, because it becomes an interesting game to balance your economy with buffs and stockpiling while one of many building of type x or y is out of commission. However I don't think it has any value whatsoever in denying the player an opportunity to use the provision house or barracks for 24 hours at level 4 and 7 days for level 5. That is just annoying people unnecessarily.