I think it's a psychological thing, you know. Someone seen some western company ended with -EX and though it's great thing. He combined it with his own name, or shortern nickname like Waldek. It turned out into Waldex. Hes neighbor seen it and thought he will name his building company this way and he called it Budex. Another low class countryman seen this pattern, so he called his car repairing company Sebex and so on...

Now you have sociological interpretation. Enjoy o/ ^^