It's horrible in Japanese. They do it so much to English words, then think that their mispronunciation is the correct way to say it. I was talking to a Japanese person and he was really surprised when I told him everybody thinks of "anime" as a Japanese word (when it's actually their version of "animation").
You are oversimplifying how the language works. For many things, there was no "original" Japanese word.
"pasokon" is a great example. It's "paso" from "pasonaru" and "kon" from "konpyuutaa," or "personal computer (PC)." There's no old Japanese word for computer (in the modern sense), so they take the English word and make it their own.
It's not like English doesn't do this. The next time you eat lasagna or pizza, think about where those words come from.
So a laptop is a "nouto" because it comes from "notebook." See
http://en.wikipedia.org/wiki/Gairaigo and
http://en.wikipedia.org/wiki/List_of_gairaigo_and_wasei-eigo_terms for more.
It is not horrible, it's the evolution of a language.