The thing is mate, it clearly wasn't intended to be a 'feature'. If the game were consistent in which spells it does not let you get scrolls for I would be content. But the fact is, it is only a select few that are affected, and there isn't a logical reason for why they would have implemented it in that way.
Mods can fix this for you, don't start shouting "GAME-BREAKING" just because there is a feature you don't like.
