[mauriciob]

I've only seen one Steam game that couldn't be bought in Brazil (I still don't know why).

I'm guessing it depends at which store you are buying it. Many of the US stores don't sell to foreigners, though. Could they be afraid of fraud?

[warseph]

I saw it in several games in Direct2Drive, (this games had the same restrictions in other online stores). I don't think is fraud though, as the same site sells other games to Argentina. This is what direct2drive says on the matter: Why are some games "country restricted" ? This is a limitation set by either the game developer or the internet distribution laws your country. We have to abide by both of their wishes.