Overpaying for unproven talent is a pretty stupid approach to an overall lack of usable talent in your system.
Why do you think teams overpay for prospects. Cause if/when they make it to the majors your getting solid production for pennies. Look at this current market baseball is in right now, Kyle Loshe and Carlos Silva getting 40+ million dollars. If paying a kid in high school or college 1 million dollars can get you a solid starter for 6 years for nothing that's clearly worth it. The entire Twins rotation makes less then Vasquez, that's why teams are willing to to pay a bit more at the draft.