I don’t think that it’s so much that math grad schools are snotty as it is that math major math (at a program that is looking to prepare students for PhD programs) is at a whole nother level above AP Calculus. And PhD Math is a whole nother level above that while the top unis tend to take the top scorers on the AIME.
Speaking of which, why does he think he’d want to consider a PhD in math (rather than applying math as in engineering or actuary work)? Has he taken the AIME? How did he do?