I understand what your saying. My cars underside was getting coated with something and I just thought the bedliner was a good choice... looks better than undercoating, good sound deadner and most of all it's easy to clean.

I've yet to work on an old mopar that wasn't factory undercoated, so I can't really say on how well they hold up without it. My ram however has nothing and being in the north and in the salt, 220k later, other than some rust, it does still look nice on the underside. So maybe it is overkill using a liner. It took me maybe 20 mins to spray the car, so if nothing else, it makes me feel better about it