In New York City, as in most of the US, I suppose, it is illegal to sell cigarettes to anyone under 18. But the law here contains a provision, displayed on a sign at licensed tobacco vendors, that requires merchants to check IDs for any customers who are 27 or younger. What strikes me as bizzare about this is, how is a cashier supposed to know the customer is under 28 before determining whether or not to ask for an ID? A store could legally sell cigarettes to someone who is 26, but still be in hot water for failing to check his ID.
The result is that shops have to ask for an ID from pretty much anyone under 40 or so. My wife, who is 36, has been carded. Now, she looks younger than she is, and someone might suspect she is 26, but there is no way she could be mistaken for a 17-year-old.