Labor union Verdi announced the strike on Tuesday, the first day of the two-day retail event. Workers are striking in shifts, so as to avoid the contagion risk of large crowds in front of their warehouses. Seven of Amazon’s 15 German fulfilment centers are affected, and the company claims there will be no impact on deliveries for Prime customers.

The industrial action is far from the first to hit Amazon’s German operations—Amazon’s German workers tend to strike around the most lucrative times of year for the company, such as Prime Day and Christmas. Usually the strikes are to do with Amazon’s refusal to enter into collective wage negotiations with Verdi, and that is a factor this time round, but not the main one.

This time the big issue is that of how workers are treated during the COVID-19 pandemic. As with strikes at Amazon facilities elsewhere earlier this year, there are allegations that Amazon isn’t doing enough to protect its staff, and also isn’t paying them enough considering the circumstances.

“Without suitable protection”

“Since the beginning of the coronavirus pandemic, employees have been performing at their best, often without suitable protection,” said Verdi retail and mail-order chief Orhan Akman in a statement. “While Amazon chief Jeff Bezos earns billions, the company scrapped the two-euro-per-hour allowance that was granted to employees from March to the end of May.”

Akman said this extra cash, which Amazon can easily afford, should be “converted into a permanent collectively secured salary increase for everyone, as the employees’ high performance generates the company’s profits.”

Bezos’s personal wealth has swelled by over $60 billion during the pandemic, which has benefited online retailers due to people having to stay home rather than browse bricks-and-mortar stores.

However, an Amazon spokesperson said in a statement that the company provides “excellent pay, excellent benefits and excellent opportunities for career growth, all while working in a safe, modern work environment.”

The spokesperson also told Fortune that Amazon has changed over 150 processes in its building to deal with the pandemic, from checking the temperatures of workers and truck drivers entering the facilities, to “organizing human flows so they don’t intersect.”

Earlier this year, there were clusters of COVID-19 infections that were associated with some Amazon facilities, but the company refuses to categorize them as outbreaks. “As with every big company, we were affected but did everything we could to support [infected workers] once they were in quarantine,” the spokesperson said.

Spy ads

Verdi’s Akman also laid into Amazon over its now-deleted job ads for intelligence analysts who can deal with (in the listings’ words) “organized labor, activist groups, hostile political leaders.”

“Employees are not fair game,” Akman said.

It’s not just union leaders who have expressed concern over those ads; dozens of members of the European Parliament last week wrote to Bezos, asking whether Amazon really does spy on “political representatives (including ourselves).”

Amazon has denied that the job posts were accurate descriptions of the roles being advertised.