Also a huge point to consider is that games also have to be as cheap as Steam. I used to buy pirated DVDs once upon a time because the real thing would cost about a month salary. Now Steam games in third world countries are so cheap I just buy a bunch I don't intend to play.
Even the discount sites and Humble Bundle aren't able to match up against Steam in third world countries.
Steam sells up to 4 times cheaper to people who live in certain poorer regions, and this also gets the usual discount. So some old game sold for $10, might get a 75% winter sales discount, plus a further 75% off in poor countries, down to about 60 cents.
It's clever because it takes purchasing power into account. So a game that's about 1 hour salary in the US would cost about 1 hour on a Indonesian salary as well.
This is going to be really hard for many competitors to match.
Even the discount sites and Humble Bundle aren't able to match up against Steam in third world countries.