Exactly. People who are good are always going to be referrals, once they've worked at a few places, their networks are just not going to let them get away. The only times I've found where you are interviewing someone experienced who turns out good is
1) someone coming from a big corporate job where they were undervalued/underutilized
2) someone coming from a different region, different country, where they have no local network
Its the old boys club. You do realize there are tons of programmers in just the US that have no contacts with the coasts? This is what makes the Ivy League so valuable which is very good at discriminating over large groups of people.
My favorite is businesses and colleges that don't take applicants from PO Boxes.
1) someone coming from a big corporate job where they were undervalued/underutilized
2) someone coming from a different region, different country, where they have no local network