Yes, and I think those problems have never been investigated fully by game designers...
While it is reasonable that 100 goblins surrounding your party cannot all attack you in the same round (probably not even with ranged weapons), IIRC AoE spells have typically been assumed to work properly. But is it really? Most AoE damaging spells allow a Dex ST for less or no damage, and Dex ST generally benefits from cover. So why should the same Fireball really affect those 100 in the area normally, why can't some of those 100 benefit from the others around covering them for example?