Honey bees do not eat honey.In fact they do not collect honey. They collect NECTAR from flowers which is acted upon by enzymes to make it honey. Then this honey is utilised in the incubation of honey bee eggs.
The function of the honey is similar to that of the mother hen warming its eggs. So that the young ones remain alive inside and hatch fast.
Anyway, good question!! but I think it would have been better to post it in biology category