A Slovak proverb (iny kraj, iny mrav).
It is not a philosophical statement of moral relativism, as the word morals is used in its original meaning (morals comes from Latin mos, moris, meaning custom).
It is a simple but very useful observation of the fact that people of different countries have different customs and that a traveller to a foreign country should not be surprised by it, let alone be critical of it.
Having lived in several different countries, and visited many more, I can attest to it being true, sometimes even in cases where the geographic distance is minimal.
For example, shortly after I left Slovakia, I lived in the Capuchin friary in Vienna, Austria. Vienna is only 35 miles from Bratislava, my home, but it is in a different country with different expectations.
I was all by myself in the refectory (i.e., the dining room of the friary), eating breakfast which consisted of some rolls, butter, and sliced cheese. The cheese slices were individually wrapped (a major annoyance as far as I was concerned at the time), so I would unwrap each one with my fingers, and put the cheese straight into my mouth, again, using my fingers.
Then a Capuchin priest walked in and had a really big fit. He used a German expression which made it clear I was doing something wrong but did not specify what it was (sort of like the English you should know better than that, but rather more critical).
I asked him what it was he did not like. Turned out he fully expected me to use a knife and fork to eat the cheese with, certainly not my fingers. I said something about it being individually wrapped. He said I should remove the wrap using the knife and fork as well.
Then he said, "Can you imagine if someone walked in here!!!" I found that question rather hillarious since we were inside the friary and only friars had access to it (and Capuchins are not exactly snobs). So, I said, "Like who?" To that he replied, "For example, me."
Now, this man was a real pain the arse, but I apologized and explained I was new to Austria and not familiar with the local customs.
He then said one of the most ludicrous lines I ever heard: "Bratislava is not that far from Vienna. The customs are the same." How little did he know!