Toilet seat covers are a total waste of trees.
Yes, someone else's butt was on that toilet seat before yours, but butts are really not that dirty. Hands are dirty, that's why you wash your hands. If your butt needed to be clean, we would have thought of ways to efficiently wash our butts a long time ago. But nobody cares. You put your butt back into your pants and move on with your life.
I'm convinced that 99.999% of covers that are used are grabbed just because they're there, anyway. People see the covers in the bathroom, suddenly think of all the other butts, and grab one.
So stop buying them. Stop using them. Start an official boycott. Every time I see them, they make me very angry. They encourage people to be totally illogical, base a decision on whether they're "squicked out" by something. That's a real problem in our world, on many higher and more important levels, that's why these covers need to go. They're not just tissues, they're a symbol of global irrationality.