Curbs on sides of roads?

So awhile back in the game towards when roads first came out they used to have a curb option. Where it would line the streets with a layer of blocks. Is there any idea why this was removed? I mean people still do this but manually now. For instance in @Banto 's Arkas, he lines the streets with an alternating red and white “curb”. So again was it removed because of a bug or did TR just think we never used that option?