Agreed but I'm like you.....old school. The reason some do it is as stated, they like the looks of a level front to back truck. The trouble with that is if you use your truck for any real work or heavy hauling you then have to install band aids to keep the truck level when you load it heavy (air bags and such)
I use mine for camping and to haul a 6,000 lb tt so I have no interest in leveling the truck. I have no airbags and even when fully loaded for a weekend camping trip, with no wdh installed, she only squats a few inches,,hardly at all, probably still has some forward rake.
If I was leveled, it'd be nose high for sure and I'd need airbags to level it out. Nothing wrong with that...just not my preference. Some guys with diesel powered 2500s need air bags even without leveling their trucks when they haul large 5th wheels with them,,due to the high pin weights of the 5vers. (Many times they are over their payload capacity but that's a topic for another day)