I take all my e-books out once a month to air for a while then carefully wash them with soap and water, rices, and air dry. I just let the reader get dirty.
All seriousness aside, at home, my reader resides in my purse. When eating out and no one is with me to provide scintillating conversation, I do not hesitate to read from it while eating. I'm just careful (I tend to avoid messy foods anyway).
I only take showers so a reader there just doesn't happen.