Well, yes there is - if the fireball is cast on you and I'm 45 feet away from you, it misses me. (and IMO it's ludicrous that AoE spells aren't subject to aiming rolls; I can't believe that in almost 50 years the designers haven't figured this out yet)
Though I do appreciate the idea of separating out weapons in terms of what they can do (and I'd really like to see a return to the 0e-1e-2e idea of specific weapon proficiencies, as an easy means of character customization), one wonders what the underlying intent/rationale behind this specific sort of DoaM/graze mechanic might be.
If the intent of this sort of mechanic is to shorten combats down because the enemies/monsters have too many hit points, then why not just cut the enemies' hit points and have done with it? (side question: does anyone know whether this will work both ways i.e. whether some monsters and-or NPC opponents will also get abilties like this?)
If the intent of this sort of mechanic is to slightly increase the PCs' odds of winning, there has to be a better way.
If the intent of this sort of mechanic is just because some players get upset when they swish on a melee attack, well...let's just say posting my opinion of that would probably get me modded halfway to hell and back.