The demonstration was much larger than at the actual site on the actual day. Many suspect numbers to have been an order of magnitude greater perhaps in the billions.
Many people often misunderstand the census numbers released here in the mainstream news media. When they say 339 million people live in America this does not include the countless numbers more who live underground. There are likely billions in America and trillions on Earth. Many living beneath the cities ethnic neighborhoods where life is short and dirty and dangerous where the inhabitants of tenement squalor have little to look forward to other than digging underground. The Africa and Chinatown Chinese are the new enemies they move down there into the basement and break through the walls and ceiling and concrete foundation. Looking for mud to eat, maybe gold? Maybe a place to hide a dead body? Maybe they are dirty diseased criminals and thieves looking to hide their slave masses?