I don't have a spare on the back, so I guess I don't need a spare tire cover.
I never quite understood spare tire covers. Is it because spare tires are ugly? I never thought of them as ugly, just spare tires. Is it to hide the spare? I know I am always mystified as to what is under that donut shaped cover on the backs of vehicles. The hard covers on old conversion vans were the pinnacle I guess.
We bought one when we were overseas because the spare wasn't in out tire rotation schedule out of recommendation from locals due to sun damage our spare is still like brand new. Here in this climate I honestly don't see a need for it other than some kind of personalization or marketing plan.