@Applicant95 This is just a hunch, but the assumption might be that if your parents are middle/upper class, then you would have grown up with the advantages of a middle/upper class student, which helps with getting scholarships for undergrad, maybe them paying for undergrad, etc. A multiplication of privileges in a sense. But I agree, it's definitely not a perfect system! E.g. parental income could be low now, but was high for many years, or maybe some students have other family members that have supported them, and so on.