This whole concept of "why people vote against their interest" is nonsense, of course.
They most definitely voted for their interest.
Sadly for them, they thought it would only hurt others.
Sadly for the rest of us, their interest was unsavory and grotesque and ignorant and racist and sexist and hateful.
I got no patience for "I didn't vote for this."
Of course you did, sugar. And you knew what you were voting for. You said what you were voting for.