Your analogy is not pertinent, surfstar. It is a policy to connect a diagnostic tool to a vehicle's computer, not a necessity for an oil change, filter change, tire rotation, etc. Enactment of policies require explicit and specific address when a mechanic comes upon a lock for which he does not have a key. According to common sense and ethics, permission must be gained to open a lock which is not yours.
Just because your plumber shop has a policy to check for and record information of expired opiates in your medicine cabinet when he services bathroom plumbing does not mean that he can ethically open your medicine cabinet to check for expired opiates if it is locked and you have not given him the key.
Also, your statement "The one example of a dealer inadvertently, etc." is mere conjecture. I have read numerous complaints across several forums of dealers deliberately completing the software "fix" for emissions without permission from the vehicles' owners, in the UK, EU and in the USA. Besides that, I would ask, at which point was completing Phase I of the "fix" on HighPlainsDrifter's TDI inadvertent? When the service department chose to upload the new software without consent of the TDI's owner? When they inspected his TDI to make sure the software took? When they slapped the stickers on it to denote competed inspection? When they demanded consent for the violation after the fact? or When they refused to restore the factory settings?
Bottom line, everyone thinks these things won't happen, even when it's evidently likely, until either it does happen or something very similar happens. I appreciate that you've read through the thread and posted a comment.