Small "shop" at the Venetian. It's actually more of a kiosk near the wall. The chocolates are decent, but nothing out of the ordinary. As for the cupcakes, skip 'em. If you're looking for pastries of some sort, walk a little bit further to behind the escalators to Bouchon Bakery. They do have candied apples, which I thought was a little weird, considering this is supposed to be a higher-end shop in a fancy hotel.
I can't say anything about the rude lady at the booth, because I have never dealt with her (although, it's been awhile since I've went).