Patriotic, passionate Brazilians have been booing everybody and anything in Rio.

MORE: What’s missing from these Olympics? Class and decency 

Their soccer-like rooting for Brazilian athletes — and passionate jeering of everybody else — has injected a brawling, unpredictable dynamic into NBC Sports’ TV coverage.

PHOTOS: Beautiful images from Rio 

The Olympics prides itself on sportsmanship. The booing has shocked Olympic officials who prefer the polite applause of British fans at the 2012 London Olympics.

We’re not just talking about Brazilians taunting Team USA’s Hope Solo over her silly Zika tweets.

The noisy booing, hooting and heckling has greeted athletes from various countries. They started by booing Brazil’s own president, Michel Temer, at the Opening Ceremonies. The cacophony of jeers hasn’t stopped since.

The fans mercilessly booed French pole vaulter Renaud Lavillenie — as he was accepting his silver medal. The Frenchman broke down in tears on the podium. He compared his treatment to that of Jesse Owens by Adolf Hitler’s Nazis at the 1936 Berlin Games.

Lavillenie later apologized for the Owens comparison. But Olympic chief Thomas Bach called the fan behavior “shocking” and “unacceptable” at an Olympics Games. 

Olympic TV partner NBC Sports has tried hard to put a good face on the problems in Rio. But even NBC’s on-air talent is shaking their heads over the crowd antics.

On Wednesday’s “Today” show, Billy Bush, Natalie Morales and Al Roker recounted the booing they experienced at an event the night before. They also cited the fans’ treatment of Lavillenie.

“He’s not even in competition. This is his moment. His national anthem is playing. And they boo him?” asked Bush.

Roker thought it was “awful.”

Said Morales: “It’s very much a cultural difference we will never understand.”

As Quartz noted:

Britain’s “Independent” asked if the Brazilian boo-boys went too far when they jeered Germany’s Dustin Brown after he injured his ankle. 

Brazil and the U.S. have a history of good relations: The U.S. was the first country to recognize Brazilian independence in 1822.

That hasn’t stopped fans from jeering U.S. athletes at nearly every opportunity.

U.S. boxers have been roundly booed. American Justin Gatlin was jeered before the 100 meter final. There was a smattering of boos as he got his silver medal.

What’s going on?

For one thing, Brazil is a soccer country. The fans are cheering like they’re at a futbol match. This is also the first South American Olympics. Many of the fans don’t know, or much care, about Olympic decorum.

But there’s also a method to their madness, says the BBC.

Brazilians like to cheer for underdogs — and boo favorites (like the U.S., which leads the overall medal count).

Sometimes they boo judges.

Sometimes they boo just for fun.

If U.S. athletes think it’s only them, they should consider the venom directed at swimmer Yulia Efimova and other Russian athletes.

At this rate, I expect them to boo during Sunday’s Closing Ceremonies.

Whatever, it will be interesting TV.