今、丁度ショッパーズのちらしが家にもあったので見てみたら、一番裏の下に小さい文字で "some of the items in this publication may not be available at all locations" と書かれています。
それに加えて、"In addition, quantity limitations may vary at individual Shoppers Drug Mart stores. Please check with your nearest Shoppers Drug Mart location for pertinent information on product availability and quantity limitations."