Normally they eat most of their kills. What is left is eaten by ravens, chickadees, eagles, coyotes, bobcats and other creatures. Death in our society is usually feared and ritualized. Often these human concepts are applied to wildlife. The act of killing is necessary for the perpetuation of a complex biological life system.
Wolves are carnivores.
They need and eat a lot of protein. Many studies have shown that wolves can affect herd numbers, but the situation is usually self-regulating. When prey numbers decline, wolf numbers do too. When forage conditions improve, the cycle reverses itself. Wolves will keep increasing until there's no game in the country.