I don't know if any car manufactures are doing this, but the technology already out there could be easily tweaked to avoid "rack accidents"

Just hit a button labelled "rack" and it could do a couple of things: 1) defeats your homelink, so the garage doors won't open from the car's button. That would be extremely easy, and pretty much just programming; 2) use the existing cameras from park assist to detect overhead hazards when the rack button is activated.

My car, and many others use electronics to detect hazards around the car as you park. It would only be a matter of adjusting angles, and programming to also cover overhead hazards with the rack on.

So create "rack mode" and bundle it with a factory mounted rack, and you've got a nice little feature to put a huge mark up on.