White tigers are not cream; they are white with orange stripes, or more accurately, a very light shade of orange.
Their appearance results from a recessive gene that causes a lack of pheomelanin, the pigment for orange and yellow. This leaves eumelanin, the black pigment, creating a white base with black stripes.
White tigers are not albinos. Albinism is a complete lack of both pigments, resulting in white fur and pink eyes. White tigers have blue eyes because the lack of pheomelanin affects iris pigmentation.
In some lighting they may look cream, but they are genetically a very light orange with black stripes.