Why do countries have so many different names?

I hate it that every country in this world has a different name in a different language. It is so ridiculous and so confusing. It would be so much easier if, like Carolus Linneaus' binomial nominclature (giving organisms scientific names that can be recognized by scientists anywhere), we simply called each country by what it's people or government call it.

For example, I will use the country known in English as Morocco. It's official name is المملكة المغربية(which sounds like Al-Mamlaka al-Maghribiya). But in other languages, the country's name is quite different. In France, it's Maroc. In Spanish-speaking countries, it's Marruecos. In German, it's Marroko. In Portuguese, it's Marrocos. All these different names refer to one country that doesn't even call itself that.

The list goes on with many other country names as well. Norway to the Norwegians is Norge. Spain to the Spaniards is Espana.

The different names of the different countries in the different languages of the world only succeeds in creating more confusion. It would be so much more politically correct and polite if we would refer to the different countries and their different peoples by the name they call themselves. It's unfair to give the different people in this world a name that has nothing to do with them and only exists because it is easier to say for the people who speak a different language different from their own.