>>1272447Old Military Jeeps and trucks had soft tops and fold down windshields partly to make them easier to fit in cargo ships and train cars for shipping and partly for ease of mounting weapons and equipment. When they started hitting the civilian market the fold down windshield was retained as a legacy feature.
A side benefit was also that the old Jeeps had shitty hand powered windshield wipers, so when it was muddy or rainy it easier to just drive with the windshield down and live with being wet.
