I have nothing against someone enjoying collecting achievements. I didn't even say I don't collect them. I've spent time trying to complete challenges in different games just because they were fun. If someone enjoys their gaming time collecting them, that's great.
What is incomprehensible to me, is being pissed off about missing one. Who cares? What does it really matter if you complete 50%, 75%, 100% or 99% of them? There is no great additional content or reward that was lost by not having a particular gwent card. It is pretty lame as far as complaints go.