Presumably they are interested in hiring students who are good enough at pure math clever enough to do well on a Math Olympiad.
There, fixed it for you
ETA actually, the extreme competitiveness characteristic of WOOTers may be of as much interest as their cleverness. At any rate, I don't think one has to posit deep applications of Euclidean geometry puzzles to finance to explain the interest! Seriously, while some aspects of pure maths do have (ugh!) applications in finance, it would be a real stretch to apply the stuff you have to be good at to do well in an Olympiad. Success here is a proxy for what they're interested in, which I think is a combination of analytical insight and performance under pressure.
