Why would that be a problem? It's an option like pano roof or other options. Just because it came included with some cars it doesn't make it more difficult to sort out. You'll likely be able to see whether the car has that option by looking at the 8.x charging screen. CPO market has dealt with it with S60's and there you actually have to call Tesla to verify (or plug into a SC).
Because when you commit to buy a CPO from Tesla, you don't get to see the car in person until delivery day. Even Tesla sales reps don't always know the full set of options on the car. So you don't find out for sure until delivery day, which a pretty high stress day to be rejecting a vehicle if you had expected the option or to try and negotiate that Tesla add it on the due bill.