Won't Waterstone's HQ be pleased when come this August a few thousand SF fans show up in Glasgow but cause no appreciable change in sales for those days? As the fen fan out from the SECC into the neighborhood (1)- including Sauchiehall St- and walk right by the Waterstones?

Not that most WorldCon book buying doesn't happen in the dealers' room, but its usually quite hard to just walk by a bookstore (even a chain) while touristing. But because its a chain the behavior of management in one store gets associated with the name, not just the specific branch.

(1)http://www.interaction.worldcon.org.uk/images/birdseye.gif