2002 Maxima gas door

My 2002 Maxima gas door lid is no longer flush with the car and sticks to a point where it is very difficult to open. Since the car is still under warranty with only 31,000 miles, I brought it to the dealer. They stated that I should have been oiling the hinges of the gas door lid whenever I did an oil change and will not cover it under warranty. I noticed that in the Altima forum that several people have had problems with their gas lid doors as well. Are there other Maxima owners that have seen this problem?

Hasn't happened in my 03 yet, but my gas door is getting stiffer and stiffer to open, I guess I'll have to oil it now.