This is THE ghetto mod but, you can get rubber golf tees, like the ones at the golf range. You can turn them over and slip them in the holes. They have a flat bottom so you'd only see the flat area on the back of the seats.
hahaah thats funny. golf tees in a golf. I have seen on the vortex some guy that has a little one maybe from an audi, that he got re-apoulstered (sp)-but he spent like 185 to do this!!! too much in my book.