Through the long term build up of conspiracytheories about jews, it is easier to blame them than most other minority groups.
Whenever a politician legitimated by popularity caused a crisis, it is a comfortable way to blame others for it.
A minority that was blamed more often is far easier to blame. People can then relate to all the other events they were blamed too. So tupid people start to belief the lies, since they are to find in enough references.
But those people who want problems solved better look out for the rootcause of the problem. And in most cases it is too unprobable, that whatever problem is vanished, when a minority group is not participating in society.