As Brian says, children being incited to break the law (by ratting about their age in test purchasing) to prove a shop is unlawful, is a bit ironic.
He feels that some of the stuff he stocks at his Silverwood Stores in Peterborough could be categorised as a grey area. He sells home brew kits that are made up of unregulated components.
I think this would be covered by the unwritten common sense rule that says, for example, if you have a skinhead trying to buy half-a-dozen cans of hairspray then he's probably going to sniff them rather than starch his tresses.
Meanwhile, Brian has come up with a nifty interactive solution. He has devised a statement for young people to sign. It says: "This is to certify that I am over the age of ..... years and can legally purchase alcohol/tobacco products. I further state that I am not carrying out test purchases for any organisation including police or trading standards. I understand that, if the above statement proves to be fraudulent, I will be prosecuted by the above-named premises."
He wanted to know what I thought. Well, I think it's a good idea. It shows a great deal of due diligence. If it's okay to fingerprint kids with the OK.ID pad, then getting them to sign must be fine. It will scare off any who aren't old enough and those who are won't mind.