Cars here in the US only has these "strips" (which are called mouldings) on the doors and body of the car. They're not on the front and rear bumpers (though there are folks that would like to get a hold of said bumpers).

When people put bodykits on, most of the time, they leave the mouldings on to save on labor costs of installing and painting the bodykit. Others have it "shaved" to have a more cleaner look. Though this is a little more difficult to achieve as it is really hard to keep the body smooth and not show waves when all the work is complete.

"Shaving" is a term used when a certain part of a car is smoothed out by removing certain things off the car and filled in to make it appear seamless. This could be mouldings, emblems, door handles, key holes, etc.

As for your dilemma, couldn't you just replace the lower front lip, as opposed to replacing the entire bumper?