It has been suggested that Apple had sales data indicating that the majority of the macpros remained stock for the duration of their initial lifecycle (i.e. first owner), and only a small number of users would upgrade their machine....
There's potentially a lot of problems with this alleged set of "data".
Granted, this isn't to say that there haven't been gobs of machines which have gone into University computer rooms which have remained 'plain vanilla', but by the same token I can say that many tower Macs that I've deployed (including personal ones) have typically been given a robust set of hardware when they were initially set up, but that this includes 3rd Party products that weren't bought from Apple.
For example, on a personal 2012 cMP, the first time that it "Phoned Home", it reported that it had 24GB RAM and four (4) hard drives ... even though when purchased from Apple, it didn't have that much RAM and only one (1) drive bay filled.
Now who here really believes that Apple's data management systems are sophisticated enough to systematically go cross-compare ... and track by serial# ... the original hardware build specifications to what it actually first booted up with? To do such a thing costs time & money, so I really doubt that their 'hardware tracking' metrics are this sophisticated.