I've been using bing as an experiment for the last three weeks or so. Google is far better for academic searches, and better support for math rendering would help extend the lead in that category. Isn't that reason enough?
Google exists to advertise. Academics are woefully underpaid. Who wants to advertise to a bunch of broke intellectuals that are just going to ignore your ads anyways?
Doctors are perfectly good candidates for ad targeting, and some are paid quite well (even at academic research hospitals). Those institutions also have quantitative science departments.