Jeff Bezos, the world's richest man, has made Amazon shareholders extremely wealthy and happy in recent years, but when it comes to Amazon's 566,000 employees, it's a different matter entirely.

Last week, Amazon finally disclosed its workers’ median annual salary, which at a paltry $28,446 put Amazon on par with Hershey, slightly above retailer Home Depot, and almost ten times below the $240,430 median annual comp at Facebook, according to recent proxy filings.

This will hardly come as a surprise: after all, most of the roughly half-million blue-collar, part-time employees at Amazon don’t make six figures while spending their workdays writing code, and instead unload trucks, drive forklifts and walk miles collecting products to fill orders—all for around the same pay as workers in other companies’ warehouses. Due to their menial, repetitive task, they are also rapidly being replaced by robots.

Which explains why Amazon CEO Jeff Bezos was booed and received a hostile reception from his own workers, when he arrived in Berlin on April 24 to pick up an innovation award (mercifully, it wasn't for making human workers obsolete.)

According to Bloomberg, around 350 Amazon workers, members of Germany's powerful Ver.di trade union, gathered outside the office of tabloid publisher Axel Springer where the awards ceremony was taking place, carrying posters demanding to "Make Amazon Pay." The union has been pushing for higher pay for Amazon’s thousands of workers in the country for several years, claiming they receive lower wages than workers in other retail jobs. Amazon workers from other countries, including Poland and Italy, also traveled to Berlin to join the protest.

In a dramatic description of Amazon working conditions, Verdi boss Frank Bsirske said that “we have a boss who wants to impose American working conditions on the world and take us back to the 19th century." Ver.di has for years been a constant thorn in Amazon’s side in Germany, organizing workers strikes to demand improved pay and working conditions according to Bloomberg.

One of the protesters at the event was Thomas Rigol, 37, who joined Amazon as a logistics worker in Leipzig in 2008. Rigol says he would like Bezos to give unions a say in the company, and increase profit sharing opportunities for workers.

"But mostly it’s about respect, which the simple workers aren’t getting from the upper management,” Rigol said. “Mr. Bezos is the richest man in the world and we are being patronized.”

The protest took a political turn, when Andrea Nahles, the new leader of Germany's Social Democrats which is in coalition with the ruling CDU, turned up at the protest, and also had harsh words for Bezos, telling reporters that he didn’t deserve his prize since he treats his employees badly. Amazon employs some 16,000 people in Germany, its biggest market outside the US.

And confirming that Germany will do everything in its power to maximize Amazon's tax receipts - if only in Germany - Nahles labeled Amazon, along with other big tech companies "world champions in tax avoidance" and told reporters that "this does not deserve a prize."

Later, during a fireside chat with Axel Springer CEO Mathias Döpfner on Tuesday evening, Bezos defended Amazon saying he was "very proud of our working conditions, and I’m very proud of the wages we pay,” including in Germany. It was not immediately clear if he discussed his unstated desire to replace all low-paid warehouse workers with zero-paid robots over the next several years.

Separately, when asked a question about whether he was concerned Trump would try to break up Amazon Bezos said he expects to be scrutinized. “The big tech companies have become large enough that they’re going to be inspected,” Bezos said. "It’s fine." In other words, "the world's richest man" does not appear at all concerned about the actions of "the world's most powerful man."