Hi!
At the time we were there, my husband was sporting a pony tail. (Middle Aged Crazies - It has since been cut off) I guess because of this, he was approached quite often. But like others have said, it is discreet, and all you have to do is say no. The Rastas, off course, believe it to all be perfectly natural, and even offered some to my 15 year old. He was a little freaked out, but when he said no, they shook hands and said ,"that's cool". He ran into them a few other times and they never asked again. They respected his choice. Didn't seem to be a big problem.