Why are Czech Republic and Slovenia clified as Eastern European countries?

For anyone living west of Vienna or Berlin, anything east of it, is eastern Europe. First it has to do with a selective history of the West, where it only remembers that this region was once under control of the Moscow (in the case of Prague) or was entirely communist. Besides, for Germanic, Roman, Anglosaxon nations, all Slavic nationalities are Eastern European. They are taught and brainwashed that entire region has a separate history from the rest of the Europe. Geographic location of Prague, northwest of Vienna or more western than Stockholm, have nothing to do with it. Majority of the Europeans have very vague understanding of geography, and people traveling from Berlin to Vienna for the first time are often surprised to find themselves to be in Czech Republic. Germans living just across border have little knowledge of the countries east of it, and they believe that entire region from Bohemian forest to Kamchatka speaks one language. As long these stereotypes will survive, and they will for another 100 years, whatever controls Prague, Ljubjana, Bratislava or Zagreb, it will be always Eastern Europe.