We use a Chevy C10 for hauling livestock. It partly gets used to pull a livestock trailer. It partly hauls a wooden box custom made for hauling dairy goats! It works for the latter job well partly because of the rubber bed mat that covers the floor. These rubber truck bed liners do a couple of things really well.
Firstly, they keep cargo from slipping around much. On our last goat hauling adventure, we ran into some high winds. Since the goat box was on the Protecta bed mat, shifting of the box was not much of a problem. If the box had been over the bare metal bed I dread to think about what might have happened. As it was, the rubber mat kept the box in place.
The non-skid nature of the rubber mats makes them really useful in many situations.
Secondly, pickup bed mats are great insulation. If you carry animals on a pickup bed, you don't want the heat from the bed to cause stress to the animals. The rubber mats are thick enough to help keep the heat down and the animals more comfortable. Mats are a good deal in the heat.
The Protecta bed mat in my truck makes it more useful as a work truck. It especially helps when hauling animals in the bed. I like the one I have a whole lot. The TrailFX is another similar liner.
That's to say nothing about protecting the bed. It's simple to destroy the metal in a pickup bed in just a short while. It's not so much scratching the paint on the bed. It's dents that really can reduce the value of a pickup truck in a hurry. Getting a rubber mat over a bed adds a layer of protection that's worth a lot, yet costs a little.
Look at the Protecta or the TrailFX for an inexpensive coating for a bed that really works well.