Beekeepers don't harvest every bit of honey that bees produce, and bees eat more than just honey. They also eat a paste they make of pollen, called "bee bread". Bee keepers that have harvested too much honey from a hive will supplement hive reserves with sugar water, but only as needed over the winter.
The answers telling you that bees don't eat honey are proof that not all the answers on here are right. Bees do eat honey. It is their primary food source. They make it by gathering and regurgitating nectar. They make more than they need so if we don't take too much they still have plenty of it for themselves.