Since apple has sold over 220 million of em, worldwide, its hardly just expats that buy them.
I never wear mine in the street, but I sure like the convenience of being able to carry 8000 songs in my pocket. I am a part timer, back and forth from el norte, so I carry a big music library with me, and its much smaller than 800 CDs would be in my baggage.
I am an extreme music collector- I have at least 1000 vinyl albums, maybe 3000 CD's, and a bunch more on hard drives- so editing down to what can fit on an 80 gig ipod, and being able to carry it around the world is very handy for me- no way could I transport my current favorite music on anything else except a laptop. And a laptop wont plug into my car stereo, the stereos in my workshop, house, or at friends houses the way an Ipod will.
But I buy mine in the US...