I have never driven past a single RV lot and saw their hundreds of thousands of dollars in inventory sitting there with covers on them.
Me neither - why? Because that would be dumb.
And yes, when I stored mine in a storage facility, you could see first hand the effects weather has on an RV. Sure - if you have the space and money for a metal building to cover it then great.
I park in full sun in my driveway. Shortly after I come home from a trip, I put the cover on it - have done so multiple times this season. Takes no time. You don't have to do that, but my caulk on top isn't sun beaten and cracking before it's time to redo it. The more you can do to protect it from the elements the longer it will last.