First time I removed the carpet in my low mileage 4/4, I found a spare pedal rubber on the floor!
After a while the pedal rubbers fell off.
I never bothred to do anything with, so I drive on the bare metal.
The rubber I keep in my desk drawer. In winter I take it out and look at them thinking of spring time.
I am not surprised they fell off, cause the rubber casting is very rough, and the quality of the rubber has properties similar to licorice.