Stats should in fact be normalized but i think it's important to understand why they are how they currently are.
From my understanding, all stats are written at level 0 because that's how they are handled by the game client. When we datamine the stats, they are listed at level 0. AS is at lvl 1 for the same reasion. Additionally, patch notes generally speak of stat changes in their level 0 values (barring some patch note inconsistencies on riot's, which have happened in the past).