Your question is a surprisingly good one, and has a far more human answer than you're giving it credit for if you're prepared to listen instead of condemning with just surface details.

I can tell you the story of my grandparents who both survived the camps. While I never met my grandfather, my grandmother lived into my mid-twenties. After the holocaust, they tried to re-start their lives in the remnants of their old town in Poland. In short time, it was made abundantly (and violently) clear that they were not welcome, that the locals blamed the remaining Jews for bringing the Nazis to their doorsteps. They were not welcome. So they looked to go elsewhere, but the UK wouldn't take them. The USA wouldn't have them. Europe in general seemed a very hostile place. Then there was South Africa, far from the horrors of the camps, where the Nats welcomed them with opened arms.