You've never been near the publishing industry, have you?
We don't use anything modern. I worked at a place two years ago that was still using B&W Macs for their typesetting. Their best machine was a 400 MHz G4 with OS 9.1. They had a lot of G3s running Photoshop.
Hell, I've been around another company that still uses old 486s running Word 97.
Right now, the bulk of my 3D rendering comes off P3s below 1 GHz.
Why? They're cheap.
If you need 50 workstations, a bunch of old G4s and P3s are an easy option.
I get my P3s for less than $30 from a local university.
Well, do the math. 50 times $30 == $1500. About what they pay for one over-priced gaming toy.