I've seen folks that use fifth wheel hitch covers when not connected and they want to leave the hitch in the bed. Guess it protects it from the weather.
I rarely take my hitch out of the truck now that we are retired. I see no need for a cover. I oil the moving parts occasionally and it's all good.
I figure if you want to spend $$$ for a cover, that's your business. People spend money on more useless items all the time
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Scott and Liz - Southern NM
2012 Wildcat Sterling 32RL - w/level up (best option ever)
2007 Chevy 2500HD Duramax
Reese Fifth Airborne Sidewinder