Settings cleared when deleting a store

I don't know if this is a bug, or by design, but I originally had 2 stores set up in NopCommerce v3.30.  Several settings were configured per each store, and when I deleted one of the stores, going down to just 1 store, all the settings were cleared out.  

I would have assumed that the settings for the remaining store would have still been kept, but I was wrong.  It appears to have reverted to the default settings.

Here's how it all went down:
1) Installed NC and created Store A.
2) Configured Store A with some settings.
3) Created Store B and used the multi-store options to overwrite some settings.
4) Deleted Store A.
5) Store B now has all of Store A's original settings and nothing that was custom to it.

Is this by design? Or am I wrong in my assumptions of how it should work?

I am very curious about this.  What setting did you loose?   Themes or what.  If you delete a store you leave products orphaned in storemapping table with no store record, so no filter for those products. Is that what you mean, that products are showing up in store B that were before filtered to store A only?

I use multi-store and it's been good so far.  But I have not deleted any stores once added.

It's by design. When you have only one store, then do not see "multi-store" dropdownlist in admin area. Hence you cannot override any setting for certain store. In this case only shared settings are used

plus scratch what I just wrote. It's not a hard map like the other junction tables, it uses entities with entity Id.  So not really possible to orphan anything.