That wouldn't be legal. There is a minimum wage of 9,35 Euro per hour in Germany. You cannot legally work more than 48,13 hours per month on a 450 Euro mini job in Germany.
I used to speed every day on my way to my under the table construction job. What's legal and what happens are different things.
I assure you such & worse also exists in my home country. It's true that the German speaking countries still have a lot of issues, but it's also true that it's much worse in the more economically right-wing countries.