“They are too stupid to see the connection.”
And arrogant. I’ve always been amazed at how so many otherwise intelligent people can be so gullible and irrational in this area.
The answer, at least in part, is while they are intelligent by society’s standards, they lack wisdom and virtue.
A fairly popular bumper sticker in Texas in the late 1970’S stated “ I don’t care how you did it up north”. The same holds true to a great extent for those leaving the socialist paradises they have created.