Why can't a remote software engineer be paid with the same amount of dollars as a regular one?

I've been asking lots of companies to let me work remotely from my country as a software engineer. I have experience in my field and I used to work abroad with companies which used to pay me a good salary. Anyway I can't seem to find another remote job which could pay the same amount of dollars with an international wire transfer to my country. Of course I would pay the appropriate taxes for my income, but the point is: why can't a remote worker working in a (usually low-paid) country be paid as much as a local one in dollars?

What are the impediments to that?