This is how I figure it: if someone held me at gunpoint and said, "I'll shoot you if you believe 100% that there is no god." Well, all logic suggests there is no god, but like many others here, I'm open to the distinct possibility that I may be wrong, so I'd tell him no, I'm not 100% certain. That's a belief.

On the flipside, if he held a gun to my head and said, "Believe in my god or die," he'd have to shoot me on principle, because I won't believe anything without proof. That's a principle.

And yes, many theists would die for their beliefs which aren't necessarily principles. I distinctly remember them teaching us about this in church, using the example of kids in the Columbine shooting who were held at gunpoint and told they wouldn't be shot if they denied Jesus (not sure if that's true or not, but that's the example they used). Point is, most believers take pride in the fact that they wouldn't turn on their beliefs in the face of death, and those who do it successfully become martyrs. I agree with your assertion, but the theist mind isn't always based on rationality. Hence, this quote.