That figure, thrown in without anything to back it up, seems truly insane. I'm British, but have an ongoing battle with keeping stuff I don't really need (and buying in bulk too), and I'm pretty sure even including all of my fianceé's possessions we wouldn't come anywhere close to 300k items. I'm pretty sure the vast majority of American homes don't contain anything like that number of items, unless you count each individual piece of pasta and grain of rice as a thing.