If anything, it would be any coating on the glass that is scratched, glass is way tougher than, well, paper. If the glass can be scratched by paper, then it is a little hopeless against air bourne dust and dirt blasting or brushing at it at 70mph. Also, you don't have to rub the newspaper on the glass like it is a polish. The idea is vinegar based windows and glass cleaner is non smearing to start with, the newspaper is the most handy and cheap material that doesn't leave fluff behind yet can absorb excess cleaning fluid. For practicality, I use kitchen roll more often as i use the cheapest stuff to buff baby lotion on the leather seats too.