Missouri merchants selling cigarettes are getting some help to enforce the national “We Card” program. They’re being given tips on how to be polite in turning down those under 18 wanting to buy cigarettes. It is illegal for Missouri store clerks to sell cigarettes and other tobacco products to anyone under 18. In fact, many of the stores selling tobacco products feature the “We Card” signs at the cash, making it clear that proof of age must be provided. The Mid-America Grocers’ Association is sponsoring a “We Card” day today, advising clerks how to say NO to young people. Studies show some young clerks have difficulty refusing cigarette sales to people of a similar age.