I have a wood cnc machine i'm replacing the ballscrew on for .. reasons

It's currently a 32mm ballscrew, with a 32mm lead.
It is currently driven by a belt/pulley setup, with gearing at 44/12.
The reduction is almost certainly being done to trade speed for torque. In this configuration, at the rated speed of the servo motors, they'll get 1000-1250 inches per minute out of the setup with 3.6 times the torque.

Here's the dumb question: As far as i know, the driving torque of the ballscrew is dependent on the lead anyway. So this 32mm lead ballscrew takes ... twice the torque to drive as a 16mm lead ballscrew. The calculations in all the manufacturer catalogs back this up. The lower lead ballscrews have no spec-wise disadvantage (higher loading capacity, etc).

So what is the advantage to belt driving this screw?
Shouldn't direct driving a lower lead ballscrew should end up with exactly the same result as this belt setup?

Other info:
The motors are rated for enough RPM to direct drive a 8mm lead or 10mm lead ballscrew at the same total speed.
You can assume the small torque difference (the gearing is really equivalent to a 32/ (44/12) = 8.72mm lead) difference that you'd get with a 10mm lead is completely immaterial.

I assume somebody decided belt drive made sense, but i can't for the life of me figure out why.
What am i missing?