Precisely, I would also expect they went to top schools. A philosophy degree from Harvard looks interesting and eccentric. A philosophy degree from a school outside the top ten or so is not interpreted the same way.

I majored in philosophy before moving to mathematics - it was phenomenally interesting, but I wouldn't be impressed by a candidate with a philosophy degree these days. A lot of people who hire humanities degrees from top schools talk about things like "diversity of thought", but I think if that was the real reason they might look for candidates outside the top schools.

I don't think that is limited to the humanities.