By allowing them to be used for hunting will just attract a lot of undesirable people wanting them to go blazing around after goats in the bush. There is no need for them in hunting when we have rifles, fact. It would also give people an excuse to be carrying a pistol in their vehicle or while deer stalking, "I was just going hunting".
By restricting them to range use it means if you are really passionate about them you can still go shoot with them.
Bows cannot hold 17 arrows and be fired on semi auto one handed, all while being able to be slipped into your waistline where no one can see it.