I believe they don't allow internet access during the build (so everything needs to be vendored, or things stuck into GOPATH); those packages are probably for the second option.
My impression is that OpenSUSE go packaging is a bit behind though. But I'm not an active packager so this may have been fixed.
My impression is that OpenSUSE go packaging is a bit behind though. But I'm not an active packager so this may have been fixed.