I concur, one can learn a lot about the culture when learning a new language. For example, in Swedish you say hello simply with “hej”. And as you may have guessed, Swedes are not big on introductory formalities even in the business context. On the other hand, German and many other languages have different words for you and You (“du” and “Sie”, pronounced Zie). As one may guess, You do not address unfamiliar people with “du”, there is a process to get to know people to the point when You ask a person if you shall switch to a “first-name basis” (this phrase gives a hint that in English, one uses the last name to address an unfamiliar person instead).

Edit: I was deeply impressed when I saw a photo of one of Einstein’s letters after he migrated to the US. Such a highly accomplished scientist still opened his letters to colleagues with “Sehr geehrter Herr Professor Dr.” (highly esteemed dr. professor, sir). This tells me all I need to know how cultured Einstein was.