I work at a McBain Group level consulting firm as one of the analysis-slaves. My colleagues hail from many different universities, but only around half are Ivy League, though all are first tier. There are 15 of us, whittled down from a field of around 3,000. In other words, for each position, they considered about 200 applications.
We might not be the best analyst, the best client negotiator, or the best excel wrangler, but in this industry those aren't the only things that are valued - the firm's profits aren't singularly tied to the strength of their recommendations. There's a certain amount of flash and pedigree that they need to justify billing out a 24 year old at $300 an hour. This isn't unique to consulting, but seems to get paraded around due to the amounts of money the position commands and the apparent inequity of taking the 'rich' and making them richer.
Think of your girlfriend/wife's hairdresser. Are they worth the $50-150 she pays them to cut their hair? Is that haircut really worth the %300 premium over supercuts or the corner store?
Based on the raw haircut of course not. But this stylist does Michelle Obama's hair, he has great gossiping skills, and the salon looks great. So she does it anyway.
There are tons of industries just like this. Why are there no ugly people in Hollywood? Why do Apple products command a premium? It's very similar to any other luxury good; you pay a lot for each incremental improvement.