Yes, these are global stats, but as someone from the third world myself, I can say that most gamers around here resort to piracy, even though steam has gained a lot of popularity, so, only a fraction of us are included in the steam statistics, which would make such data not very representative.
Perhaps a better source for understanding software usage in the third world is data from statcounter. They show something around 3 to 5%, a much higher number. However, even this data can be biased, because they only count machines connected to the internet and who browse certain sites.