Are you *seriously* suggesting using an easily spoofed MAC address is one way to do that?
No, and I remind my employers of this pretty much monthly to try to push towards 802.1x/MACSec on the wired side. However, we already use (password-based) 802.1x on the WiFi side, and you can't gain anything by changing your MAC after WPA2 enterprise authentication because your encryption keys and AAA state are tied to it, and trying to use someone else's for a fresh authentication isn't something the controllers abide. Which is why the Apple tweak doesn't try to touch anything but probes; it would be completely dysfunctional if they did it on actual traffic.
Also in our case your IP is locked to the MAC and ARP traffic is properly inspected and filtered (you'd be surprised how many WiFi systems do not do this.)
So yes, our network relies on a feature (802.1x auth and WPA2) which "means less privacy for users" in the sense that we know who is using what machine, for what, and roughly where. You would be hard pressed to find an enterprise network that did not.
As far as what we use it for in house, it's to improve the odds that each client has virus-checked each of their IOS or Windows devices individually (it is more trouble for most of them to learn how to change a MAC address than just to update their virus signatures, so this works well), and, as mentioned above, the controllers do location-based roaming optimization to unstick sticky clients, and that last part it what the Apple changes have the potential to break. We do carve out exemptions for network troubleshooting, deployment planning, and for stuff like locating lost or stolen equipment, but for the most part our policy on location tracking data is "don't look at that data and throw it away promptly."
Now, if this feature does become a problem, I sincerely hope Apple bothered to put in a user-accessible control for it. Given they seem to be of the mindset that the more user control they can take away from their WiFi setup the better, that hope is pretty bleak, and we'll be lucky to even get the ability to tweak it via a .mobileconfig.