Default locale in console commands is always en_us rather than the site default
Turns out this is actually a bug, too.

It's going to end up being more involved to fix than a build release probably warrants, though, so it'll have to wait for the upcoming 2.3 release to get a proper fix.

In the meantime, you'll be able to get by with your workaround of manually setting it.

$c-&gt;locale = craft()-&gt;i18n-&gt;getPrimarySiteLocale();