I call bullshit. I'm calculating how much I eat per day and it's barely 2000, sometimes a little more, sometimes a little less. And I constantly struggle with "some" fat around my belly and waist despite I'm fairly active compared to my compatriots. And since these numbers are showing the average (were children calculated in this?) that means there are people out there who's energy intake way over this amount.
Tho the wiki article's intro suggests these numbers contains the wastage as well.