bcspace wrote:Doesn't this also mean that someone with nothing to do with a particular calendar could subscribe and receive notifications not directed at them?
What do you mean by "someone with nothing to do with a particular calendar"? If its a ward/stake calendar then anyone in the ward can and should be able to subscribe to all the calendars no matter what organization. If you only wanted select individuals to view a specific calendar then there is the option of making a private calendar.
Here is the information from the calendar helps about setting up private calendars.
"Private Calendars
You can choose to make your calendars private. You may want to keep your calendar private, for example, if the events include the bishop's appointments, personal priesthood interviews, or families you are visiting as a presidency. When you make your calendar private, you must select the viewers who can see the calendar's events. Note the following about private calendars:
Members can see event blocks for private calendars on the calendar, but they cannot see the name or details of any private calendar events.
Administrators can see the editors and viewers for the calendar. However, to view, add, or manage the events on the calendar, administrators must be added as an editor or viewer. This security restriction ensures the privacy of the calendar.
Private calendars are intended for Church use, not for personal family calendars.
As with other calendars, if the person creating the calendar is not already an administrator, private calendars are sent to administrators for approval."