Depends on the hotel. At the HI in Sanford, NC no post and i walked in each week for over one year OC'ing. No objections, recommend then 100%.
All others I have never seen a no firearms posting. If I did I would not stay there more than once. I've been staying at a lot of places for work and not seen any postings. I will not look further than the door. Not at any rules or web site info.