Perhaps a nominal fine closer in value to those motorists might have to pay, plus the pilot paying the costs resulting from their actions might be more effective. These costs might rightly include those incurred by commercial operators having to break off their approaches.
I don't think it helps to fuse criminal and civil law in that way. If the commercial operators suffer loss because of the negligence of an aircraft operator or pilot, they have the usual remedies available, don't they?
Fines are fines. There's an argument to suggest that they should be linked to real
safety risk, but not to commercial loss.