Bats do have eyes. Fruit bats have very large eyes that help them navigate in deep darkness and find their preferred foods. It is only the group of bats known as Microchiropterans that rely mainly on echolocation, but even these bats have eyes.
Although Microchiropteran bats do not rely on vision as much as other animals, their eyes are still present and functional. These bats utilize their unique echolocation abilities to sense the world around them but still use vision to help them when echolocation cues are confusing or difficult to pick out due to background noise. Fruit bats, on the other hand, use sight and smell rather than hearing as their primary senses. Both groups of bats have very good night vision but poor visual acuity, similar to that of a rat or a dog at best. Only fruit bats appear to have color vision, as indicated by the presence of special color-sensing cells in their retinas.