Yep our mittens growl when they have something delicious, like raw bones, cheese, cucumber or a large slice of cabbage stolen from the compost bin (yes I know, they're wierd). It's to warn each other off. They don't do it when they're eating normal dinner, just when they have something they consider to be a treat!
And our Harry loves hairbands. The thick elastic ones with a lil bit of metal? We have tonnes of them around the house and I never saw them as particularly dangerous xx