Just because its weird does not mean its wrong.
I really cannot see anything in the rules or the FAQ to indicate that we should not treat scenery as models. At a common-sense level we buy build and paint them as models and the rules never try to say anything to the contrary.
What the FAQ says which does not directly answer the question but clearly indicates their approach is
Q: How is terrain intended to be used? Simply to block line of sight and/or for the use of warscroll rules?
A: Citadel scenery models that have warscrolls can either be used in accordance with their warscrolls or follow the rules for scenery on the Warhammer Age of Sigmar rules sheet. Scenery models that do not have a warscroll use the rules on the Warhammer Age of Sigmar rules sheet.
So
scenery models throughout that answer.
Things which are part of the battlefield are different - e.g. hills. We are told that they are not terrain and are part of the battlefield which strongly implies that we are not to treat them as models.
So if it is weird I think that is because the rules are weird rather than because this is not the correct application of the rules. Unless someone can find something I have missed.