Bit idea: Person who thinks that wiping with water and toilet paper is not sufficient, insists one is not truly clean until they've wiped the area down with rubbing alcohol
I use a small towel that I hang by the toilet specifically for this purpose. I guess if I had other people using my bidet I would have a big stack of them and throw them into a little hamper after a single use or something, but they only ever touch my butt and I make sure it's squeaky clean before drying so I just change the towel out once a week.
Look, you're the cleanest thing in your house at that point. So your towel is only ever getting cleaner. It is such a waste of precious resources to wash it.