From Mashable:
Making the Twitter rounds on a super-sized scale today (under the hashtag of #seriouslymcdonalds) is this obviously fake sign that's allegedly in a McDonald's restaurant. It claims that "African-American customers are now required to pay an additional fee of $1.50 per transaction." The picture originated on twitpic and has gone viral from there.
A tipoff that this is a fake? We called that 800 number you see at the bottom of the sign, and it connected to the KFC Customer Satisfaction Hotline. But really, think about it: Would any McDonald's franchisee or employee tape such a sign on the door of a McDonald's restaurant? It would be career suicide.
Read more here.