That's really just not sensible is it.... You'd think at a minimum they would contact the driver and advise them to return immediately or their vehicle would be immobilised. I've heard of vehicle lease and finance companies using immobilisers if the user has fallen way behind on payments and won't respond to communication which to me seems the only real application (along with theft) and even then it should be when the vehicle is motionless so that they can come and retrieve it.

Hi. Yes we're a supplier (albeit hardware agnostic but we do supply some devices). I'm sure Peter knew I'd be wading in, uninvited :) Because I'm passionate about knowledgeable advice based on real experience. We are not fans of Spot devices in a commercial environment.

There are a number of independent reviews which have been done; copy and paste the link below for a really thorough review.
https://www.outdoorgearlab.com/topics/camping-and-hiking/best-personal-locator-beacon