MARK_CREATED and rendererType are special properties. Both are more related to the real UIComponent instance, which means those properties does not change for components inside a table (h:dataTable rowStatePreserved="true").
In the case of MARK_CREATED, almost all components created by facelets uses it, and this is assigned when the view is built. It has only sense to save this value when the component needs to be restored fully, but since this is a property that does not change once created, it does not have sense to store it on the delta.
In the case of rendererType, the same as MARK_CREATED happens, but by the spec, it could be valid to set a ValueExpression for it and it is feasible to create a component, call markInitialState() and then call setRendererType(...), so this value could be saved on the delta.
Components that are created without properties (for example h:panelGroup) only require these two properties, so storing these values at UIComponentBase it is possible to prevent create unnecessary Map.Entry instances.