Inn accoutrements, while not necessarily part of an adventure, can add some interest to the game.
Each set of colours has a different potential for amusement, distraction or value. A complete set, if you could find one of any given colour, would be at least two full table settings of glazed china, goblets and glasses for each setting (with or without jewels to enhance the effect), a table-cloth sized piece of material, a place-mat sized one and one not much bigger than your average doily.
For example, a rich miser might use one colour magical cloth for all his sales dealings and another for his purchases. The different colours would affect the value of his items, up to sell and down to buy. A rogue might find the same magical cloth, or one that affects things differently. Someone with a low charisma could use a magical set of cups to try for more favourable outcome in an information gathering session.
Conversely, a merchant might have a gold-coloured cloth for his items and people would assume that the price was too high because of the effects of a magical cloth of the same colour. Only a "detect magic" spell would be able to tell the difference. On the plus side of that, though, having an item placed on a magical cloth would reveal the proper value of the item, not necessarily the price at which the item was offered for sale. These are just guidelines, however. Feel free to use them as you see fit and if you have any other ideas for items, feel free to contact me and I'll include them in the list.
For the technical minded, yes, these are all doilies that I've crocheted or knitted myself. ;)
Peg