Those places do care about school name to the same extent. You'll get a junior position there, if you have a Harvard/Yale/Princeton degree, but you're not advancing unless you come from a well-connected (and likely wealthy) family. Attending a top-tier school is often just a proxy for wealth and connectedness. The companies you mentioned keep the prestige of the company high by hiring from the Ivy League, but the unconnected hoi polloi end up doing shit work for a decade until they figure out they're in a dead end.
