Maybe the previous owner added the zip ties...
Right, there are two screws into the tank and the bottom bolt that goes into radiator/guard. On the plastic there is "plastic nub" that also goes into the radiator/guard. There are two holes in this "plastic nub" that you can thread a zip tie through and go around the hole with the groment that the "nub" goes through...
Hopefully my explanation makes sense. I rode without it ziptied on that upper attachment and didn't notice the plastic flapping around, so I guess this is an unneeded mod someone did.