The super high endowment per student colleges on the list are often less expensive than in-state publics, not just out of state publics like Michigan, which has a sticker price of $84-$88k for out-of-state. Some advertise as less expensive than in-state publics for >90% of students (>90% of high school grads in US, not 90% of the mostly wealthy attending students). Many are ~$0 cost to parents for families that are not far above median US income, with typical assets.
For example Colby is on the list. For families with typical assets, Colby claims a cost of $0 for families with $75k income, and no more than $20k net cost for families with $200k income. https://afa.colby.edu/cost-and-aid/