Thanks, martizzle. I've never limited myself in my scope of studies. I think it is more that others have imposed their limits on me.
Physics & mathematics is seen to be rather versatile, since it is heavy on quantitative. I know that many go into Finance and Economics at the grad school level. However, I know of very few people who have switched from Chemistry to another field (may be academics do not consider Chemistry as training you to do something transferable?).
I guess I am not interested in just putting marketing plans in place, but to better understand and develop concepts that aid marketing. That is not quite what industry wants (they want the plan and execution), and hence my hope of getting into grad school and getting into academia. Looks like I have to rethink my strategy...