Nick did run a little differently than the others especially when Changed. For most, being pet wasn't something they'd ever stand for. But even as a person Nick liked to curl up and be pet, and liked doing it in return. For him, it was no different as a wolf. He rarely got the chance to interact with people in that form, the rest of the Pack usually the only ones to see him at all and when they did they'd usually Changed too. Being pet as a wolf was rare.
He just cast a look at Kate, kind of smug as if to say she wished she'd thought to wander right up and get scratched.