Collective bargaining

About five years ago, a book store fortuitously appeared next door to the coffeeshop, replacing a wine store.  I'm not a wine-drinker, so I was thrilled.  

It's a bit like a Tardis, looks quite tiny from the outside, as you climb the entrance steps, which are painted to look like book spines. (The titles change every few months.). Inside, is much what you'd expect: books on one side; small gift assortments, i.e. bookmarks, reading glasses, cookies, etc. on the other.  But beyond, are two large rooms:  one for used books, and a much larger day-lit room with new books, games, journals and other stationery.  (My particular weakness.) At the end of a corridor with cards for every occasion - some of them quite rude - is a closet stuffed with jigsaw puzzles. There's a puzzle exchange every few weeks; people line up for it.  It's that kind of neighbourhood.

In December, I buy stocking stuffers.  The rest of the year, I mostly buy cards, stocking up every month or so.  Recently, I lay my choices on the cash register counter, in order to rustle up my loyalty card.  The cashier totted up my selection and mulled over what collective noun would work best.

"A kindness of cards?" I suggested.  "No, wait!  A communication of cards!"  She was clearly taken with the former.  I prefer the latter.