Conditional group defaultValues being saved to document object even if condition isn't true.

I have a few groups in a collection that appear conditionally based on checkboxes, and within those groups, I have some text fields with default values. I expected to see either no group saved to the document or, at most, an empty group object if the condition wasn't met when I added a new document to the collection.

Even though conditionally, the groups are not active when I save a document, is it expected behaviour for the group & default values to be saved on the document object?