It sucks that you were sold an 21+ band to later get kicked out and beat up. I think you've waited just a little to long to make anything out of it. With that being said why dont you and a group of your friends go back with some hidden cameras and try to catch the bouncers selling 21+ bands in the bathroom and buy one. Then go out to the bar and ask for a club soda with lime and drink half of it. All you have to do now is take a swig of mouthwash and act tipsy, not drunk. For even more of an effect you could brag loudly how you are'nt 21 and you just bought the bracelet in the bathroom from a bouncer. This will more than likely cause the bouncers to treat you the same way that they did before, as they have an notoriously bad reputation. Then contact all of the local news stations. Im not telling you to do this but, it would be awesome and karma is a bitch.