Lip stains and cheek stains serve the same purpose. However not all cheek stains can be used on lips as they might not be lip safe. Some brands like TBS ensure that their cheek stains are lip safe thus marketing it as a lip/cheek stain. However, if you see from the recent MAC See-Thru Colour collection, they had seperate lip and cheek stains. Lip stains coming in a tube like the usual lipglasses and cheek stains coming in a different packing which allows it to be applied more easily on cheeks. So, although lip stains and cheek stains serve the same purpose -- which is to "dye" the skin in a very natural looking way -- they may not necessarily be the same thing.
Also, lip and cheek stains definitely come in a variety of colours. Perhaps if you check out other brands besides TBS you'd get a better idea of the variety of the available colours. If its possible, look up on MAC's See-Thru Colour collection (of which the stains are unfortunately LE i think) and they'll give you a good idea about other types of stains besides those from TBS!
HTH!!
