RV tire covers are definitely NOT a frivolous investment. Some accessories might be optional or nice to have. But not these.
You need to protect your investment in your travel trailer or RV, right?
Tire covers do just that. The sun and weather can damage your tires over time especially when you are not using them.
UV rays are extremely damaging to rubber tires because they accelerate deterioration, causing them to harden and crack.
You don't want to be driving on those! And you don't want to need new tires if you've only used them a few times.
So protect them with tire covers!
You can find covers for each individual tire or you can cover them in pairs if you have tandem axles.
Some tire covers are made of canvas and are breathable. Others are made of vinyl with a flannel lining.
You can even get "designer" tire covers that are color coordinated to match your RV. It all depends on how much you want to spend and how picky you are about appearances.
The fasteners are important, too. If they aren't strong enough, you'll lose your covers to the wind one day.
Some tire protectors slip over the top and you use bungee cords to hold them on at the bottom.
They may come with the bungee cord or you may have to provide your own. Factor this into the total cost when you're comparison shopping.
If you don't already have a source for RV accessories, you can find all kinds of choices at Amazon or eBay.
Just pay close attention to the sizes, take good measurements.
Then ask questions if you don't see everything you need to know on the item description.