We sorta have more area to cover, more remote areas than smaller countries like Great Britain, Japan or Israel.

I live in a rather rural area and honestly AT&T is about as good as it gets around here. I could go Verizon, but they're CDMA based and I tend to travel overseas.

And that's the other problem. Only two of the biggest four carriers in the US are GSM.

And to further fill you in, since it seems as if you're speaking only from your experience overseas and have little to no experience about the seriously fragmented and technologically behind-the-times carriers in the US... there's no benefit to jumping around with an unlocked phone per carrier in the US. No discounts, no incentives... just a higher priced phone that you can remove the sim and carry over to a new carrier... if they're in your area and support that frequencies of that phone - which, is hardly never. A phone that works on T-Mobile doesn't work on AT&T at native 3G speeds. And vice versa. It will have to degrade to slower EDGE or EVDO or worse... GPRS and the like in most cases for data.

It's not like it was in Japan or Germany when I lived there as it is in the US. The carrier system here plain sucks. That's why the archaic system of subsidies still exist here and just about only here in the US.