Just to be a pedant, that's not what was stated: "As a workaround, you can use your zip code instead.".
Your assumption is that zip code == "U.S zip code" which is a fair assumption if the site only supports the U.S. Other comments on the thread shows the site does support locations outside of the U.S. It is therefore also a fair assumption that it _might_ support similar functionality outside the U.S., kuschku simply tested said assumption and stated that it was incorrect so that other readers were aware.
Your assumption is that zip code == "U.S zip code" which is a fair assumption if the site only supports the U.S. Other comments on the thread shows the site does support locations outside of the U.S. It is therefore also a fair assumption that it _might_ support similar functionality outside the U.S., kuschku simply tested said assumption and stated that it was incorrect so that other readers were aware.