Each region has its own Server Cluster, and when codes are generated it takes a while to make sure that all codes are implemented across all the servers. So some codes will go through the extra steps to be a World-Wide Code, while other codes might be less formal or more ad-hoc, like for a local-language Community Stream.
Anyone is welcome to watch and get drops from Community Streams regardless of what language they occur in, but it's fair to assume the codes given out are intended for the primary viewer base of each Community Stream. The free stuff is meant for their folks!
Our English-speaking Community Stream for the NA Server is typically on Wednesdays at 5pm CST, so I think we try to make sure any codes we have are readied for NA and EU servers, because we commonly get viewers from Europe in the audience as well as North America folks.