Mine were barbed plastic. Just pull harder and they "zip" out. Most wont be reusable or very good at holding tightly. I got a bag of replacements form auto whatever for a gmc. Just need the shank to be the right size.
Just snap the plastic clips off and replace them. I removed my hood insulation years ago. Has not hurt my paint at all. Figured I dont need to hold MORE heat in the engine bay, and its neat to watch rain turn into steam when it lands on the hood.
Have used these to replace broken clips on other hoods: