I know what you mean--I get these comments too, and I've been living in places like Germany, Belgium, England, Mexico (Mayan Riviera ain't as cheap as you'd think) etc., while earning dollars, and still making it happen.

People always ask how I can manage to travel so much and live independently when my take-home pay is so low compared to a salaried developer. The answer is that just like everything in life, it's about priorities. One person might prioritize cable TV and an iPhone for $200/month, whereas I'd put that money to a plane ticket. Granted sometimes things like babies or health problems don't give you a choice, but for many people, it is a choice to be chained to desks job they hate.

Don't know about living costs in Japan, but I've lived in Thailand and Russia where doing a bit of remote consulting and a bit of product development earned me around 2000 USD a month without a whole lot of sweat.

In those countries, it was more than enough to live well above average. Taxes are naturally also much, much lower which have a large effect.

At the moment I'm back in Europe for a contract. 2000 USD while living here? After 50% tax, that's only enough to cover half my rent! Techies in low-cost countries really do have it easier, as they can price their products / services to an international level, while still having low local prices.