with a great respect to engineers and job They do...
I must say I don't like You sitting on my seat with no protection cover.
Car engineers use it always I go with my car to make an inspection. Is it so difficult for some of You to put a sheet of material on the seat before you put your a.. on?
You use this seat for a while to make papers or ( happens now and then) to repair the thing that calls for you knowledge but ... we use it for much longer time wearing white shirts!
I always clean up the cockpit before I leave it ( bottles , papers, fruit cores etc - the staff I may be responsible for) and the cleaning service is not always allowed to enter the deck and use vacuum in the vicinity of the knobs and switches ( happened to inhall...) - so tell me who is to clean the hidden parts of the decks? all these small compartments for things like torches, landing gear emergency extension handles etc?
and guess who inhalls that filthy air for 10 hrs?