thinkware f100

Hey guys, Why is the "Rear Infrared" Camera cable so short (It's about 1 foot long)? I bought this unit from DashCamBros ( https://dashcambros.com/products/thinkware-f100-dash-cam?variant=4807387611167 ) and according to their website, it says: The Regular Rear Camera comes with a 18 foot...