Experience of foreigner about Germany

You described it very well.
But there are stealer in super markets, you just don`t see them.
And, yes. They are very cold people.
Wedding is often just for financias reasons.

It is very sad, but it is like the way it is.

i told this to my German friend and she told the same as you, and ask me to be alert with my bike aslo. You are right Simon

Hi Ngocanhkdqt,

yes, the customs are a bit different - I can attempt to interpret some of it for you (with disclaimer of course).
It helps to sometimes interpret the cultural legacy by looking what a large group of people fought to achieve over an extended period of time:

1) Serving with a smile: How much does a smile really represent the quality of the product you're buying? How much should it? In Germany this is not necessarily related. You are right that Service (or the perceived unwillingness to provide service) is probably the biggest shock - for most people both Western and Eastern Culture visiting Germany. Let’s look back - the person selling their stuff were historically a "Meister" - you would come to him/her at the shop without a glimmer of specialist knowledge. He/She was an expert in this area and emotionally de-coupled from any brand, would consider many trade-off based on your explicit (and implicit)  criteria and would provide you with an excellent objective proposal that fit you like glove. Since he/she saw the different products everyday, especially those returned broken, his/her experience was worth gold in terms of long term value. Showing emotions (similar to the pleasure of seeing an old friend), is flattering but not honest.This behaviour is another form of Keeping Straight Face (Japanese called it Shirankao, Chinese mianzi), with the exception that it is with pride between two equals and there is no servant. Today this has been replaced by people with trained servant smiles, paid different commissions to cajole you - independent of the quality, and never seeing you again later with complaints or returns. Ideal for commercialization but not necessarily good for you.  Of course, we, coming from other countries, have been "trained" differently - and see this decoupling as plain offensive. Sun Tzu learns in his Art of War – offense is a personal choice and hence a personal angle of weakness. So rather look for the benefit this brings.

2) What some interpret as coldness other would consider respecting your privacy and being a unique individual – ie your individual right to not be "dragged along in a stream". Same goes for respecting you as equal, whether you're a man, woman, independent of orientation, belief, race, family & social background – European citizens have strong roots in an egalitarian society (UK + Common Wealth, US is distinctly flavored differently) (French Revolution and the birth of democracy a good example in old Europe). Notably Northern Europe ranks higher Egalitarian /Hierarchical than Southern Europe (source Hofstede: Cultures…) and this pervades in even the simplest everyday acts:

o    it is socially and professionally acceptable if the husband takes 6 months off for parental leave instead of his wife.
o    everybody shares in the fun but also equal in paying the bill. So it’s much more than the financial cost of the festivities, but on the long term welfare and  reducing burdens caused by social traditions on any individual. There is a choice. More importantly, no one needs to feel gravely offended for life if they're not invited (at least that the theory )
o    A woman can equally pay for a meal than her male counterpart, and although it is flattering, it can be offensive if the male counterpart believes that his companion cannot return such favor at own choice.
o    Husbands may work shorter hours to do their 50% of the house chores.
o    your ability to marry without religious customs or rituals,
o    Your ability to choose whether you want to a festive moment with a relative you only know on a photo or with a friend of your chosing,
o    Your would never whistle to a lady passing by on the street in Northern Europe, whilst in Southern Europe a lady may feel unnoticed if her beauty is not confirmed.
o    The narrow salary span between some managers and experts,
… the list goes on and on.

In fact, I belief some of these “rituals” is very deeply rooted and pervaded long before the Romans conquered parts of Europe with their disciplined patriarchal hierarchical structures, from earlier epochs when some Germanic & Celtic tribes had a matriarchal & egalitarian bouts at the turn of the last ice age. That doesn’t mean that other cultures have it better or worse -The perception of “correctness” is just a scale with many arms and different weights. So what you interpret as offensive behavior is just weighed differently.

Look at it like this - there are offensive behaviors we bring as foreigners to Germany, sometimes without knowing that it is offensive :

1) Refilling your glass of wine without doing so for others around the table. Cutting the front end of a cheese when the cheese plate arrives.
2) Not making eye contact on a beer Prost.
3) Spitting in the street
4) Carving your name on a national monument / site of heritage
5) Continual sniffing
6) Relieving oneself in public rather than paying 70c
7) Pointing fingers to individuals of lower business rank
8) Shouting at subordinates
9) Not talking during dinner
10) Long explanations why you can't accept an invitation
....

Make a choice to embrace this difference as another type of freedom.