I believe glue. I have really ugly silver wheel arch and door moldings, will remove them in a couple weeks when I have a free weekend and can get other things taken care of at the same time. When I bought the car I should have asked the dealer to take them off (got used from dealer), stupid me!
They are clipped on the ends have all blue clips and the strip has white flat circle pinch clips. I repaired my OEM mding . I suggest you access from the BACK. Do not try the tool to fit under the strip. You will break the clips! Access to the tiny one remove front wheel well and reach up and pinch to remove. The door ones not sure if you can remove the door panels then the weather tight material to reach. When I fixed and painted the one side I ordered the OEM entire 3 pieces for the strip and pryed then off. Painted the strips with dupicolor flat black bumper paint. You must wash new trim with a scuff 3m pad to remove the manufacturing layer then prime and lightly scuff then 3 coats 10 min holding can 1 foot away to insure an even coat. Then snap in new trim and your done. I hate shopping carts!