Because red F40s are just so common.
If there is a car that exists that looks good in matte green then you can be pretty damn sure it is not the Ferrari F40. Ferrari only made these cars in red, and while a recent example was spotted in blue that actually looked pretty sweet, this is nothing short of an abomination. Others may find the camouflage green look a pleasant change from the norm, but then not everyone has good taste. Thankfully a paint job can be easily changed, and that's exactly what should happen here.