There is no other way of putting it! I do apologise in advance. I am not trying to offend anyone here. But in comparison with other nations, Germans are (generally) not polite to strangers.
Before moving to Germany, I had heard this many times but thought this was a stereotype like you hear so many about different cultures and people. Having lived all of my 20s in the U.K., I may have got used to politeness and being over-polite a little too much, but after almost two years here, I do feel this is mostly true.
The other day, we arrived at the supermaket and parked in a family-reserved space. If you are not familiar with these spaces, they are great when you have a child in the back as they are wider: you have enough room to open the doors to let your kid(s) get off and fiddle with their seatbelts, etc. They are near the entrances. But they are also very sought after and getting one is almost always impossible. We parked up and even before getting off the car, a man started shouting insults at us (which we didn't understand but could tell from his tone they were not love words). He muttered something we understood that included "kinder" (children). My husband opened the door and starting saying "yes, I know. What do I have here in the back safely tucked in her car seat? Oh, right a cute three year old, also known as a child!" But the man didn't let him. He just walked off continuing to moan. Lovely! He was obviously upset before he even knew if we had a child in the car. As a side note, the normally rule-abiding Germans often do park in these spaces even without a child or any sort of child seat in sight. Maybe he thought we were such a couple!
More generally speaking, people are not polite as they don't smile at you easily, they don't step aside to let you pass them on the sidewalk, they don't smile back at a child trying to make contact with them, they don't care about hurting your feelings.
And I do not feel it is only about the German language being more direct than the English one, as some claim. In English there are so may words and so many ways to ask for something indirectly or politely. 'Please' and 'thank you' are used for everything. The German language is admittedly much more direct and straight to the point, yes, but it is not a matter of language. It is also in people's attitudes. Of course, there are exceptions and once you start to know them, they are really nice people. But at first glance and to the stranger in the street, they are rude.
Another recent example, at the airport. We were sitting next to a German couple. The place was packed, so no spare seats. My daughter was on my lap. Inadvertently, while playing, during a silly move, she touched the man's trousers. She didn't hit him or punch him, just slightly touched it with her feet. I apologised but the man proceeded to brush, tap and clean his trousers for the next 25 minutes without responding, muttering a word or a cracking the slightest smile. What was I supposed to do? Clean his clean trousers? Pay for dry cleaning? I'd rather my daughter played while in the airport than she screams in his ears on the plane for 5 hours!
Another German expat is saying the same thing here and attempting to explain why the Germans are rude! Ok, he is living in the U.K. And may have been corrupted by their manners too...