So, you know how sometimes you’ll go to the store to get beer and you’ll see six packs that are missing a few bottles? Somebody has bought a mixed six pack (and inevitably they’ve bought half the bottles from the last six pack of the beer you wanted). I always wondered if there was any etiquette behind that, and last weekend I got to ask a nice shopkeeper about it. He explained that in his store you can mix six packs as much as you want but they’ll charge you a single-bottle price for each bottle in the pack, meaning, for example, instead of $8 you could pay $12 for a mixed pack. Taking a few bottles out of a last six-pack is rude, but for all the swapper knows there is more in the back. If the beer you came for is victim of missing bottles you can negotiate a normal six-pack price with replacements.