I removed all of the warning stickers when I first got my trike. It didn't come with any cable frame protections...I didn't even know there was such a thing. With a trike there is a lot more steering and cable rub around the neck, so in no time the cables would rub the paint right off. I cut long thin strips of velcro with rounded ends and put them on both sides of the neck. (Rounded for looks and not as easy to catch on the cable.) I also used it any place my bags, etc. would be rubbing on the frame.
So anyway, for me if I took off the frame protectors for whatever reason, I'd put something back there.
Bob