Yeah I've considered this too actually. I was kicking around the idea of relocating to Vietnam for a while this way. I wonder how much more difficult working remotely from that far away would be. I imagine there are programmers already living in places like that that would be happy to get contracts at first-world salaries, so hopefully being a native speaker and understanding first-world cultural conventions would be enough to justify asking first-world salaries.
Professionally I think you can leverage your knowledge and first world status better if you move to a place with people who speak better english (the Philippines/India/Malaysia) and with a larger outsourcing industry (the Philippines/India/Malaysia). Unless you by native speaker mean native Vietnamese speaker, that could be an awesome advantage -- wages are for workers in the outsourcing industry is, among other things, determined by english speaking ability. When it comes to getting first world salaries where you do contracting work is probably often irrelevant -- and could also be hard to tell (depending on need for communication making time differences or unstable internet connections problematic etc.). I have been wondering about the possibility of being a sort of salesman/manager/quality controller for contracting work with Filipinos doing the grunt work. (The Philippines and Malaysia does not tax foreign sourced income, wich could go a long way to offset a decrease in pre tax income.)