Well you'd have to ask them, wouldn't you.

What I am saying is that you should consider that maybe these people are not innumerate - they could realise that the policies they are voting for will harm them but they believe that it is the correct thing to do.

Some people think that federal taxation in general is morally wrong and should be reduced. Whether you or I agree with that is irrelevant if what we're debating is have these people realised that it could help them but still think it's right to vote against it.