Salaries in different countries

While being in Ukraine I wanted to find out how is situation there after Orange Revolution. Despite people are optimistic, but changes are coming really slowly. First what I saw in the Lviv airport it was old soviet system of total control and humilation of people, annoing lines and strange questions. I talked to a taxi driver, who was really talkative and happy to tell about his town. That day he paid final sum for his taxi car, so he was really happy. But you know that in Lviv avarage salary is about 80 USD?! It's not a lot at all... Well, I know you can compare capital cities with towns in regions, but still for ex. in US they have much higher salaries and level of prices is lower than in Eastern Europe. How is it possible? I don't know...