I received a heavily wishlisted book today and there is staining on the edges of the book (if you hold it closed and look at the outside of the pages).  Possibly just dirty hands, but one of the pages is stained.  None of it appears to be liquid/moisture damage. 

I personally would never send out this book, but does it warrant RWAP?  Or am I just too danged picky?

the help center specifically states no stains of any kind.  i would definitely mark it RWAP.  it is up to whether or not you ask for your credit back.  i probably wouldn't in this case, just because a small stain might have gone unnoticed by me as well.

i recently received a book for my keeper shelf with staining on the sides, and i asked for my credit back since it was a keeper.  i got a nasty pm from the sender, but she did give my credit back in that case.

i recently received a book for my keeper shelf with staining on the sides,

Many times, the discoloration on the edges of the pages is normal aging, or foxing.

http://www.bookologist.com/cab/abu/y203/m03/bk0001/s03

That is allowable.

Stains from ick, or coffee, or chocolate, etc. are not.