I think it's normal for startups to try to get things for free, be it software or work hours, and that's OK up to a point, but once a company reaches a plateau of business activity and operational maturity then it becomes a sign of poor management that they can't balance workload and workforce.
Out of curiosity, are you German? My experience with German companies was centred in the financial services sector out of Frankfurt and some tech companies out of Munich and overtime was never even suggested so I'm thinking there might also be some differences between the regions.
I'm not German, but we've been living in Berlin for about 2 years now and lived in Vienna for almost 8 years before that.
I was even explicitly told by some companies when interviewing that they expect and encourage workers to stay until at least 7-8pm...at least between Berlin and Vienna there is definitely a difference in attitude.
Out of curiosity, are you German? My experience with German companies was centred in the financial services sector out of Frankfurt and some tech companies out of Munich and overtime was never even suggested so I'm thinking there might also be some differences between the regions.