[OJFord]

And they've tried 'any price' (even not taking it facetiously literally)? What makes it so unattractive?

The prospect of working on Bing or at Microsoft wouldn't exactly excite me perhaps, but it'd only have to be the best paying (by some non-trivial but not massive amount) offer. (Or everything else less exciting!)

Perhaps you mean search engine experts, not grad entry or 'at any price' in that sense, so the pool they're looking at only wants to work on the biggest most exciting one, which happens also to be willing to hire all of them?