Forum .LRN Q&A: Deleting 'cal_item' does not delete 'acs_activity'

Just want to get some opinions before I submit a 'Bug

I was looking at calendar in dotlrn 2.0.3 and it seems that when you create a cal_item, an 'acs_activity' and an 'acs_event' are created.

But when you delete the cal_item only the acs_event object is deleted. The acs_activity object remains.

This is the case with recurring cal_items as well. Is there any reason that these activities are retained?