"For “the biggest climate rally in history,” attendance was remarkably sparse. Those of us in the Light Brigade guessed 5,000"

The Light Brigade Shines at the Shivering Blackout Rally

It was really, really cold the whole time. I was surprised that everyone we ran into was wearing oil-based clothing. I figured a couple people would try to symbolically wear “natural fibers,” I didn’t see any. When I pointed out to people that their clothes were made of oil, they blamed “the system.”
...
For “the biggest climate rally in history,” attendance was remarkably sparse. Those of us in the Light Brigade guessed 5,000. We were heartened by the lack of real enthusiasm by the protesters. The Light Brigade, as our videos will show, had real passion–we love energy with conviction, while they hate it with confusion.
“Forward on climate” was personified by the shivering, emotionally muted, and fairly sparse crowd leaving early in their oil clothing to get to their coal and gas homes.
The lesson of the protest was clear: Nature, untamed by fossil fuels and other affordable, reliable energy is an often uncomfortable and dangerous place to be. That’s why the protesters left as early as they could, and why the whole production was ridiculous. Who wants to stand outside in the middle of February, freezing to “send a message” about “global warming”? Resolve faded to the point where by the 4:00 closing time, I could shoot footage right next to the stage with no one within 20 feet of me.

Stunning: 40,000+ Rally in DC for Forward on Climate | 350.org

What a day! Over 40,000 people poured into the streets of Washington, DC today to push President Obama to take our nation “Forward on Climate” and say no to the Keystone XL pipeline.

Our team here at 350.org had expected a crowd, but this was MASSIVE. Volunteers from around the country organized 130 buses to get people to the rally and it showed: there were people of all ages from Florida to Wisconsin to California here today.

Washington DC Climate Rally – February 17, 2013 « Suwannee – St. Johns Sierra Club

Contact our bus coordinators to sign up for a seat on the bus. We are asking everyone to contribute $72.74 towards the actual cost of $130.  [So who paid the rest of the "actual cost" and why?]

Charter Bus Prices and Bus Options

[Typical capacity around 50 people]

It seems highly unlikely that all the buses were chock-full of people. 130 buses at 30 people per bus would be about 4,000 people. If 36,000 other people actually attended this rally, how did they get there?