Well to them, the Japanese culture and language is boring everyday stuff. After all, they grew up hearing of and living through it. But to them, European and American stuff is really fucking awesome and new, and they like to dabble in that.

After all, to them it's new and nifty. We're just bored with it because we all grew up strongly influenced by French, German, and English. To us, those languages are dull and only mildly interesting. Yet we perceive Japanese language and culture as new and fascinating, simply because it's had very little impact on us... until recently.

Gotta look at things on the other end of the perspective.