Indeed, saw a lift in London last week that had a capacity of 13 people, but a maximum weight of 800kg. That's 61.5kg/person, or 135 lbs. Not sure that's realistic in any group of adults in the western world.
I can't think of any elevator placard I've ever seen where the rating was something you could realistically exceed. You'd need a "some tradesmen moving a big piece of equipment" or "highschool sports team sardine packing themselves in there for amusement" type of situation.
