You test out the limitations of your inventory system by seeing how quickly you can snatch up a whole mess of silver. You zip around as fast as possible and snatch up every piece of shiny bric-a-brac you see lying around. You successfully add One (1) Pile of Silver to your inventory. That THAT, logic! The chest is a bit too big and wedged into the trees to get grouped in with the rest of the pile, but you're not complaining about your haul.
It's so convenient that all of this treasure was just left lying around here, completely unattended by anyone else. What a great stroke of fortune that isn't worth questioning at all!