Casino sister sites can be extremely useful if you are seeking an online casino to play at. These sites are, in most cases, the exact same as the real casinos and offer players the same casino gaming options. However, they do not have the same advertising expense, so they cost the operator's less money, and it is possible to play for free with these sites, provided you are able to find a good site to play at. While there are some real casinos that offer online casino sister sites, there are also many legitimate websites that offer quality service, but are simply trying to exploit the goodwill and fan base of the real casino that they also own.