Take a look at the Sargent seat. It's got a piece of felt that doesn't seem to cause any damage. My 06 had this bad with the stock seat. The 05 I bought had a stock seat, but it didn't have this issue. Of course it did have a couple of minor scratches. So I guess I'm saying buy an aftermarket seat or try to put a piece of felt on the seat to keep the problem from getting worse. As long as you can't see it, it doesn't bother me. But to each their own.
I had the same issue on my 06- the foam stickers on the bottom of the seats were not lined up properly to cover the seats staples so the staples ground through the paint of the tank.
The dealership replaced the tank under warranty and put more sticky foam over the staples.