It should work in the same way as the original storage items, but doesn’t seem to exhibit the same kind of behaviour. I’ve added this to the database.
Correction: It’s working as expected. Locks protect the entities adjoining the block the lock is attached to. The only exception is the open storage (shelves) which can be accessed and also protected as a group. Closed storage can not be accessed as a group and hence isn’t protected as a group.