I never understood why some of our dogs get this and others don't, considering they all have access to lounges, beds and non-hard surfaces. I have been told it is actually a fungus and you need to treat it as such. You don't necessarily have to use cream from the vets, but I can't remember the name of the cream I was told was suitable from the chemist. Sorry to be not much help, and I'm not saying it isn't caused by hard surfaces - just that I have been told from several sources it could be something else.
Katrina