Game show contestants who bore on and on before giving their answer: "It can't be A because ... bore, bore, it can't be B because ... yawn, yawn, yawn, so it must be C". Just give the answer, Trevor.
Also game show contestants who start every sentence with "So" (especially looking at you, Pointless).
People (always men) who just stand in the doorway of a room, gawping, and not sitting down.
People who constantly say "obviously" when there is nothing obvious about it. Bit similar to the "like I said" ones.
People standing and yacking on the pavement with their backs to you, taking up all the space. And can't or won't hear you when you say "excuse me", forcing you onto the road.
But I don't get the ones about not having your purse / card ready at the checkout. Usually the first chance to get it out is when you have packed. Too busy up to that point.