A man in his late twenties dressed in black with long hair tied in a ponytail is a little reluctant to admit the truth.

Yes, he explains, he does work in the vast container-like "Fulfillment Center" across the street at Amazon's logistics hub in Leipzig, located in a part of former East Germany that has seen a rash of xenophobic demonstrations.

"It's not something that people here think of as a good thing," he said.

The 75,000 square-meter (807,293 square-foot) warehouse employs around 2,000 people in a city with an unemployment rate of 9.5 percent - almost 3 percent more than the German average. This holiday season, another 1,400 workers will get temporary jobs in the massive building, handling the crunch of Christmas orders.

The extra work should be welcome but some employees are frustrated with their employment at Amazon, the world's leading global online retailer that has turned Germany into one of its biggest bases outside the United States.

For about three years, the Seattle-based behemoth has been the target of Ver.di, Germany's biggest labor union group, which wants Amazon to adhere to Germany's collective bargaining agreements instead of using its own pay system. Since 2013, the union has organized industrial action at Amazon plants across Germany - where it operates nine warehouse centers like the one in Leipzig.

The union's demands are specific - Ver.di wants Amazon to pay its workers under the collective bargaining agreement used in Germany's retail sector, which guarantees a higher starting wage than in the logistics branch, and to hire more full-time workers instead of relying on part-time contract employees.

Amazon has refused to buckle under to the pressure, despite a drumbeat of negative press in Germany where the U.S. company has often been held up - unfairly says Amazon and some of its own employees - as a caricature of the heartless American employer that reduces its workers to anonymous drones, underpaid and unloved.

But the battle is not untypical of the corporate cultural clashes that often occur when U.S. and other foreign companies come to Germany, where in many cases workers are represented at the highest levels of corporate decision-making, and unions such as Ver.di, Germany's largest coalition of unions with 2 million members.

The union has appeared to settle in for a prolonged fight with Amazon.

In 2013, some Ver.di members traveled to Seattle to protest their case outside the company's headquarters.

Amid charge and counter charge, Amazon has thrived and expanded in Germany, which is now the company's largest single market outside the United States.

In 2014, the U.S. company generated sales in Germany of €10.7 billion ($11.9 billion), about 13 percent of its $89 billion globally. Back at home, Amazon came under fire again after the New York Times this summer exposed what it described as a "toxic" white collar working culture.

In Germany, the relations between Amazon and Ver.di have been fraught. Ver.di has regularly held strikes over the last few years to push its central demand that workers be brought under the retail collective bargaining agreement. Amazon has responded that its workers belong to the logistics branch, but are paid well for that industry in Germany.

In Germany, Amazon said it is creating opportunity for people who would otherwise struggle to find work.

The company's job center is open to anyone and prospective employees don't even need a resume on recruitment day.

"Everyone gets a chance and then we check out how they work here," said Dietmar Jüngling, the stocky, fit manager of Amazon's enormous Leipzig facility, a career logistics professional who used to work for Procter & Gamble in Germany. The selection criterion, he said, is to be physically fit and to speak English or German.

Amazon employs 12,000 people in Germany, making it one of the country's largest foreign employers. At most of its logistics centers in Germany, Amazon pays its non-management workers about €10 to €11 per hour.

Workers generally start at 6 a.m. and finish at 3 p.m. In Leipzig, Amazon gave employees the option of structuring their own break schedule. Employees there chose to divide their times into a 20-minute and 25-minute break per shift.

A night shift works from 3 p.m. to 10 p.m.

Germany accounts for about a third of Amazon's 29 warehouses in Europe.

The entrance to Amazon's warehouse in Leipzig is fortified with high gates, employee screening machines and beefy security guards.

Theft is often a problem at large warehouses like these. One Amazon worker, who was provided by Ver.di but requested anonymity, told Handelsblatt Global Edition the problem was caused by Amazon's cavalier approach to hiring workers.

"If one chose employees a little bit more carefully, trusted them and gave them a fixed contract, then one wouldn't need those big security gates at the entrance," said the worker.

It is during the Christmas holiday season that most theft occurs, the worker said.

Mr. Jüngling told Handelsblatt Global Edition that Amazon staff are trusted, and the security gates are there as a precaution.

"We have a low theft rate here," Mr. Jüngling said. "This is not only because of the security gates upstairs. Our biggest security are our employees."

Disputes over whether Amazon takes enough care of German workers continue to simmer in the background.

Mr. Jüngling, the Leipzig plant manager, said Amazon prides itself on constantly improving its efficiency and making processes run more smoothly. While this may please customers and boost profits for Amazon, some workers say that the efficiency drive goes overboard, at the expense of workers.

In Pforzheim, for example, some workers are collecting signatures from Amazon employees to change the composition of the factory's workers council, who they say are too close to the company and not listening to worker complaints.

One employee who works at an Amazon logistics center in Pforzheim in southwest Germany said she feels threatened by having to wrap and unwrap plastic packaging from huge, 2-meter (6.6-foot) high pallets often stacked with 15 kilograms to 25 kilograms (33 pounds to 55 pounds) of goods.

"I am 1.64 meters (5.4 feet) and weigh 50 kilograms (110 pounds). What about safety?" said Corina Rauscher, a 48-year-old employee who was provided for a telephone interview by Ver.di. Ms. Rauscher said she is not the only short employee at her center who feels endangered working with the large pallets.

She said she has injured herself three times since working at the plant over the last two years.

After one accident, she said she was unable to move her hand as fast as before when she returned to work. Immediately, the responsible supervisor put her under pressure to achieve her usual production targets, regardless of her injury.

"I already had 3 accidents at work! My hand hurt and I could not work as fast as usual," said Ms. Rauscher. "Immediately a lead (manager) who knew of my injury asked me: 'You know why I am here now, don't you?' I said 'No' and he said 'Yes, you do!' He knew I had an ailing hand! And then as punishment he made me work the 15kg packages the next day," Ms. Rauscher said.

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