Cabin Air Filter Frames

[Merkava_4]

Hey guys, I'm just curious why cabin air filters are available with the frame if you want it; do the frames wear out? The cabin air filter frame in my Buick seems to be made out of good sturdy plastic; I don't see how it would break or wear out.

 

[raytseng]

some people may accidentally throw out the frame.

just like how wipers technically can just be the rubber strip or the whole frame.