Humans give animals value as food, as ornaments, and sometimes as components of an ecological web.
As food, it does not matter that the individual animals suffer amazing amounts of torture before their death since their value is after death, and the suffering generally correlates with efficiency and more end-product.
As parts of an ecological web, the animals have to have be in substantial numbers for some equilibrium to be reached. Game reserves aren't good examples of that.
So big-game hunting "preserves" animals not for food (I don't think people eat lions, and at any rate it is amazingly inefficient food), not for the ecological web, but for ornaments. These animals literally exist to please us aesthetically, and then get shot. We're not preserving the species out of some respect for nature, but so that a handful people can see them instead of in pictures, and an even smaller handful of people can kill them. Saving species is not a worthy goal in itself without trying to recreate a proper balanced ecosystem. If they are in a balanced ecosystem, hunting would not be necessary.