Cockpits in club planes or line aircraft in commercial ops are some of the must unhygienic places on earth. So many small switches, knobs and bezels that when the pilot coughs or sneezes it is almost impossible to quickly wipe the panel. The result is no-one ever does. Layer after layer builds up and is combined with the carbonized drink spatter and the odd coffee splash. I was part of a club years ago that had about 30 people sharing a 172. I swear, some of the dirtiest truck stop bathrooms ever encountered were cleaner.
Oh yes, the glamour of the aviation world…