I do agree with you here, and we will probably rework this in the future. It is just not on our todo list at the current moment.
The reason it was implemented the way it was was based on feedback from our users when we had the 3.0 version in beta. That is what a lot of users asked for so that’s how we did it. But it does seem a little bit much and it would make more sense that you control all of the group calendar settings (or at least the ones that make sense) but right now we just don’t have that on our agenda.
You can see we have already added this to our GitHub: https://github.com/moonstonemedia/Simple-Calendar/issues/101
You can definitely spark some conversation on the topic there as well if you would like.
Sorry I can’t give you any ETA or anything like that on this right now, but it is something on our minds that we need to think about when we get there.