in may ways is the brand, many people around the world see the US as the ultimate place to visit/live.. The territory is also like a continent in itself. the american culture it's been the strongest for more than a century.
of course there are economic advantages compared to the 3rd world, but non are exclusive to the US, far from the best.
bitcoiners tend to focus on the bearish economic aspects of the US, Canada, Europe, etc.. but then when you're there, you remember that reality is way more complex