"It's not!" Harry insisted, his emotions carrying away with him again. "Voldemort was evil. If you followed him and believed all the rubbish he taught and hurt people in the name of it, or even helped people that hurt others, then you've done something evil. There's no 'point of view' about it. There is good and there is evil and it's your choice which one you side with. Having a family that supported Voldemort did not mean that you automatically had to mindlessly follow him too."

Sirius hadn't and neither did his little brother after he realized what was really going on and the Black family was as about as Dark they came, obsessed with the 'pure bloods first' creed that Voldemort taught. Both of their sons had ended up trying to defeat Voldemort. There was no excuse for what Bast had done, even if he had just ended up watching the Floo, he had still done something terrible.