He already explained it. His step-dad decided to buy a brand of candy which is well-known for its peanut-flavoured varieties but he didn't think that was worth bringing his glasses along to read the label, and even after he got home, where his glasses were available, he still didn't read the label, and instead just assumed it was okay for his step-son to eat it. No doubt the real reason he's collecting donations is for the defence of the upcoming negligent homicide case.