Celebrities not using bitcoin just looking forward with their chance to get much money become advertising and promoting bitcoin to public, they will become advertiser with everything although with ponzi scheme when receive higher payment and reward, its the same case in my country where many celebrities promote with scheme ponzi site and now have scam.
Whatever they do is none of our concern, but if they start advertising Bitcoin that would be a very big initiative in the spread of this digital market in the whole world. Public follow their styles and their ways of living. If they will start promoting this market that would be very beneficial for all of us. The development will attain more speed and its usage would be spread to far flung areas.