I do buy second hand shoes from charity shops and Ebay - due to financial restraints at the mo! :( I make sure they look clean first though, but some are like new, such a bargain especially ones made by M&S and Next. I wipe them out with Dettol anti-bacterial spray and it doesn't really bother me. What did bother me was years ago on a special Anniversary holiday to the Caribbean (I had money then as worked in those days!) we went snorkelling on a reef, we had to wear communal plastic shoes they stored on the boat so we didn't cut our feet on the coral ................ but then the diver brought out the snorkels kept on the boat and that thought of other people using them with bad teeth, colds or smelly breath really made me gag ........but I used it anyway, glad I did, the sight under the sea was the most fantastic experience of my life.:)