I have some fieldwork experience (roughly, latitudinally from the Arctic circle to East Antarctica, and Longitudinally from US to Australia). Yes, I have scratched both bin and camera glasses. I have actually smash an Swarovski glass that had to be replaced, a pair of zeiss Jena that are now just part of decoration, and a couple of cameras that ended up in the bin. I also broke a swaro STS80HD on fieldwork in Heard and Mcdonald island.
Shit happens, it is a matter how much you use a thing, how intense, and of course, bad luck.