I am going to make another point of which I feel I can. When my two were teenagers and started going out to pubs/bars/clubs – the MAIN thing I told them was to NOT leave their drinks at any time. This hit home BIG time. They both have a drinkie poo before they go to a club, and then drink water, down in one – so, aboslutely no chance of anyone spicing their drinks (also, I pointed out that it doesn’t cost anything!).
My point being – it is up to the parents of the youngsters to educate them. I don’t give one iota if someone says they have no control – that is their fault in the first place.