Here, I’ll help you. Legalized hunting is a program based on scientific wildlife population management. Why is this necessary, you ask? Because ignorant, irresponsible humans wiped out most of the natural predators which previously managed prey populations. Therefore, it becomes our modern responsibility to manage prey populations using our intelligence and highly developed ethical systems. If a population grows too large, they can change the way forests grow, which can alter the flows of rivers. There are countless unpredictable knock-on effects to consider. Invasive species like pigs destroy land, plants, and other animals, often endangered.
Examples you might consider are the wolves of Yellowstone and the sea otters of Puget Sound. Those are natural predators that were reintroduced to manage invasive over populations of deer and sea urchins respectively. In many areas of the world, it is unfortunately inadvisable to reintroduce natural predators such as wolves, bears, and large cats. Therefore the responsibility lies on humans to maintain herds scientifically. And yeah, probably the best people for that task would be volunteers who enjoy the hunt and don’t waste the remains of the animals they take, who respect their quarry and pride themselves on a swift and relatively painless kill.
Poaching is illegal for valid scientific reasons. Poachers do not respect limits and kill all they can. They kill often just for trophies to sell on the black market. This negatively affects populations that scientists are working to maintain. Consider when hunting was unregulated, and racist assholes did their best to wipe out the buffalo in order to starve the Native Americans. Animal torturers like this sick f#ck exhibit serial killer behavior and need to be managed by the justice system.
Finally, it sounds like you consider predation to be unethical. I’m not sure if you realize that predation is part of the natural order of things, and cannot be altered by any known means. Most prey animals in an unaltered environment will die in agony to tooth and claw. Most predators find killing pleasurable. Any that didn’t would go extinct. My pet housecat, for instance, cannot be given a vegan diet without slowly killing it, no matter how much I dislike buying animal products. Maybe you disagree with the concept of pets, hell, I don’t know. Then you have to deal with the massive feral cat population somehow, and they kill like 10 billion birds a year.
Besides complaining about the injustice of it, what alternative solutions do you have to offer the Real World? Humans happen to be animals – top predators who survived and evolved by hunting. You cannot get around that fact, but we can moderate ourselves and manage it responsibly through science and the law.