> Do you also tell new car owners to demand a new car when their windshield or paint gets dirty? >
Your analogy is quite misleading, comparing a car windshield to a camera sensor. One is externally exposed all the time, the other is hidden and delicate. Certainly, a new car just out of dealer would go to the details and get clean all around unless it is from "Black" market. The original post was a two-week-old new camera unless it is not a US model. For out of warranty one, people then decide if they want to clean all the time like you or not.