Bees are not afraid of milk. In fact, they have no particular reaction to it at all.
Bees are insects with biological needs very different from mammals. Milk is designed for mammalian young and offers no nutritional value to bees, which obtain their energy from nectar and pollen. There is no evolutionary reason for bees to be attracted to or fearful of milk.
Milk could potentially harm bees by promoting bacterial growth or interfering with their hydration. The idea that bees fear milk is simply a misconception with no basis in bee biology or behavior.