"Why do we academics want students that have taken a lot of math? There are several reasons:
1. Every economist needs to have a solid foundation in the basics of economic theory and econometrics, even if you are not going to be either a theorist or an econometrician. You cannot get this solid foundation without understanding the language of mathematics that these fields use.
2. Occasionally, you will need math in your job. In particular, even as a policy economist, you need to be able to read the academic literature to figure out what research ideas have policy relevance. That literature uses a lot of math, so you will need to be equipped with mathematical tools to read it intelligently.
3. Math is good training for the mind. It makes you a more rigorous thinker.
4. Your math courses are one long IQ test. We use math courses to figure out who is really smart.
5. Economics graduate programs are more oriented to training students for academic research than for policy jobs. Although many econ PhDs go on to policy work, all of us teaching in graduate programs are, by definition, academics. Some academics take a few years off to experience the policy world, as I did not long ago, but many academics have no idea what that world is like. When we enter the classroom, we teach what we know. (I am not claiming this is optimal, just reality.) So math plays a larger role in graduate classes than it does in many jobs that PhD economists hold."