(I don't have enough reputation to add this as a comment). As mentioned, they are for luggage. They are also typically required to recieve a certain star rating by the different companies that release star ratings. For example, the catalogue of criteria for Hotelstars has item 115 for "Adequate place or rack to put the luggage/suitcase", which is required for 3 star ratings and above. If this wasn't included in each room then the hotel might get a lower number of stars.