When you see your favorite celebrities drinking your favorite drink from a can, there is absolutely no guarantee that everything is quite as it seems. Apparently, it is known that a number of these companies have a tendency to go ahead and produce cans that just contain water as they know that the celebrities do not believe in drinking energy drinks due to their health routines. They are then given these cans of water so they are then able to parade around and give publicity to the company.
Clearly, this is cheating, but it is far more widespread than you would perhaps like to imagine. Of course, they would also turn around and say how amazing the drink was and what they love about it. They are meeting their obligations, but it is not always the case that they are completely upfront and honest about it all.