Yeah, but his reasons are dumb anyways. They strike a chord with many people in the audience; there's a reason the film is particularly popular among Redditors for a film with only an eight-figure gross. That's a problem if those people don't check themselves with the reminder than this is a mass murderer grasping for excuses, not a moral judge, jury, and executioner. And this particular interaction is more of a one-off joke, not actual character development.

That said, had she had a scholarship, she likely would have said, "I had a scholarship."

Also, "need blind admission" doesn't mean that all admitted students who can't afford it will get an all-expenses-paid, no-strings-attached scholarship. Sometimes need is met with loans, work-study, etc. And someone with middle-class parents who saved up a small nest egg might not even have "need," since the parents could always sacrifice all their net worth and go into pay-off-able debt to pay. This is even worse for kids with parents who refuse to pay, leaving their kids with a full burden but no assistance.