Correct, how "official" is a facebook post?

A local restaurant we frequent was doing a holiday gift card giveaway via their facebook page. I entered and the next day I got a facebook message indicating I had won. Only problem was so did many others as their facebook page had been "cloned" and the only noticeable difference was an "apostrophe as in (')" between the two words of the name of the restaurant. A good example of how things can get messed up using social media for "official" announcements.