On one hand, I can understand a young person who maybe wasn't cooking much beyond simpler stuff or at all when they were living at home (and then potentially was living in dorms in college, so once again got food from the cafeteria and not cooking in their dorm) to make this mistake. Maybe you've seen a person plop a pizza on the middle rack without anything (which seems to be the norm for many frozen pizzas).
But then on the other hand, man you'd think something is terribly wrong in your process if your oven is half flooded in grease and blood.
Verdict: I'll let it slide.