They call themselves Uber Drivers United. Yesterday a video surfaced of Mario describing today's event and inviting drivers to join them. He expected 1,500 to 2,000 protesters. The reality is far less. Maybe 150 protesters showed up and listened to their leader air his grievances. The core issue is the dwindling amount of money they're taking home. Mario tells Engadget that someone at Uber leaked information to him that a $.50 per-mile rate was coming ahead of the Super Bowl. For drivers already struggling with the fact that their take-home pay is less than when they started, it's a powerful rallying point.

When you talk to the protesters, most won't give their last name for fear of retribution. "I'm in the system," John tells me. He's a representative of a limo drivers organization that supports Uber Drivers United. Another driver, also named John, says that he started driving 18 months ago and was making $300 working eight to 10 hours a day. But as Uber has slashed prices, he's working 14 to 16 hours to eke out $150.

"Who made this company a $60 billion company? Drivers!" he tells the crowd.​

One after another, the drivers complain about how their weekly take-home has gotten smaller and smaller. The shared sentiment is that Uber wants to run Lyft out of business so it keeps slashing prices. When asked if the recent winter price cuts resulted in more riders, they all shake their heads.

Megaphone in hand, Mario riles the crowd up. "Who made this company a $60 billion company? Drivers!" he tells the crowd. He keeps hammering that they "have them by the balls" and that the $.50 per mile he heard was coming will arrive before the Super Bowl.

Uber has told Engadget that it is not lowering its per mile rates to $.50. The company also announced that it will raise the per-hour guarantee to $35 an hour during core peak hours while the Super Bowl is in the Bay Area. But the long-term damage is done and the crowd is itching to get on the road.

Uber has been the target of protests from drivers and cabbies both in San Francisco and elsewhere. All drivers are considered contractors so they don't get the same protections as employees. The Seattle city council recently voted to allow Uber and Lyft to unionize. Unfortunately, federal law prohibits contractors from collective bargaining.

Their first stop is the parking lot at SFO (San Francisco International Airport) where Lyft and Uber drivers wait for fares. It's full before the protesters show up. The idea is to recruit more cars to the caravan before heading into San Francisco. The plan seems to be to circle the lot honking their horns and blocking traffic. It works. By the time they convoy heads in to the city, roughly 40 percent of the parking spots are now empty. Some joined, while others may have just decided to move on to get riders at another location.

The drivers at the SFO lot are also less than forthcoming with their names. A few drivers say they just joined Uber so they're not interested in protesting. Two drivers tell Engadget that they'll join if the entire lot empties out. "We support them, but we have to make money," one said. "This is the third or fourth time they've protested and nothing has changed," the second adds. They've both been drivers for over a year.

Like the other drivers in the lot, Paul has been driving for Uber for over a year. But he has no interest in bringing traffic to a standstill. "I understand why they're protesting, but it is what it is," he said. Uber is his second job and not his main source of income. Like other drivers, he's seen his take-home pay get smaller and smaller since he started. While he's not going to protest, he thinks the winter price drop ahead of the Super Bowl is unethical.

The convoy hits an Uber office in the Potrero Hill area of San Francisco. They circle the block honking and disrupt traffic exiting highway 101. At this point it's tough to determine who is part of the protest and who is stuck in the snarl the caravan has created. Everyone is honking either out of frustration with the ride-share platform, or the traffic.

San Francisco traffic is already a mess because of the upcoming Super Bowl. While the protests are blocks from the city streets that have been closed for the event, as traffic tends to do, it's rippled through the streets for miles. A throng of 200 or so Uber drivers is making it worse.

The drivers circle City Hall horns filling the air before eventually showing up at Uber headquarters on Market street. Mario, megaphone in hand, talks about drivers living in their cars. He tells the story of an Uber driver that lost his legs in an accident while driving for the company. He says Uber won't cover the guy's medical bills. Meanwhile the cars silently circle the block. The police have started handing out tickets for honking. They've been shadowing the group all day.

Mario keeps yelling at the building. He told Engadget that he tried to set up a meeting with Uber CEO Travis Kalanick. The company head never got back to him. So the city of San Francisco can expect to see more of Mario and the Uber Drivers United group. They're already planning another protest during the Super Bowl to fill the local highways. "We will shut it all down."

Update: Uber sent Engadget the following statement: "Seasonality affects every business and Uber is no different, so when holiday parties wind down in SF that can mean a slow start to the year for our driver-partners. By cutting prices for riders, we can give them one more reason to take a ride, which helps keep drivers busier during the slow season. To put drivers' minds at ease, we have hourly earnings guarantees in place."