I would say yes, it is a modification to the vehicle that did not come as standard from the factory on youur model.

Not sure if it would cause an issue in the event of a claim unless it was a theft claim, but you never know.

However, those kits take all of five minutes to take off, not suggesting it is a great idea but in the unfortunate event, they could be removed before the car is looked at? Also, they aren't a giant garish kit so may well get overlooked.