Is there too much of an emphasis placed on the PHD in academia?

Stated another way, is there some quantifiable difference between those who seek master's degrees and those who seek doctorates? If there is, does the difference justify the current distinction between the two?

The distinction seems like a product of institutional culture rather than anything practical. But that's just my view as an outsider. Regardless, I'd love to get y'all's insight in this matter.