Not quite sure about this, I was an MECP certified master installer for a few years and during that time (80's&90's) I saw no remote starts that came with merc switches. We would have to install these supplementary. We also made magnetic ring switches that encircled the shifter and bypassed the remote start if it were in gear. We also did one with a hydraulic resevoir and pump that applied the clutch during the start sequence. I think what the issue is for dealers and shops, is that back in the day when remote starts were new, certain ones (DEI) had issues with starting when the battery was reattatched. This is not an issue with any current systems that I know of. There are plenty of shops that do not install any type of bypass or safety switch for the hood with remote starts. It is unfortunate, but it does happen. And also, the owner of the car incurs the liability of the damages in most states, not the shop that installs it. I am finding out all sorts of neat things since my wife went to law school. It's kind of like trying to sue a gun manufacturer because someone shot you. Very difficult if not impossible.
Britt