I can't see why it should need an independent feed from the battery either, all the power it needs is available at the front of the bike already.
However, if you do hook up extra wires to the battery it's important that they include a fuse as near to the battery as possible. Without that, if the cable gets pinched or chafed and shorts to ground somewhere, there is nothing to limit the current, the wire gets hot and you have a fire under the petrol tank. Admittedly, you seem to have extra sleeving protecting at least some of the cable, but an in-line fuse is always good practice.