I've read that these cheap OEM licenses could be cancelled after some time. Dunno if true or not. Could you give a link for EU courts' rulings?
The ruling was appeal and a 2016 ruling in a higher court just confirmed that you can in fact resell software licenses.
That said, sometimes the licenses can indeed get cancelled. I’ve seen a really sketchy looking photocopied label that a guy “got” that didn’t work. Depends on the channel perhaps.