Harsh hazing and initiation rituals are a pretty effective way to build team "spirit" and make people believe the group they've joined is special, and being a part of it makes them special or better than non-members. It may or may not be part of why FAANG interviews the way they do, but it is likely part of the outcome.

Well they do pay a bit more than 15 dollars an hour. Hard to not feel good about that.