I did not word my reply correctly. The intention was that I obviously do not see it as a good idea puttting a dog in a boot without light, ie that of a saloon and not a hatchbag or estate car.
I appreciate owners have dogs and see them as part of the family. It is reassuring that you use a harness to reduce the likelehood of injury to your dog or passengers. I wish other owners were as responsible as youe are.