I get what you're trying to say, but you are a little misguided.
Yes, people do hunt for the thrill of it. It's just the same as any other outdoor activity, save for the detail that sometimes an animal dies during the process. However, you would be mistaken to think of hunting as some primitive, blood-drunk thrill (even though it may be for a select few). I haven't gone hunting for a few years now, but when I did, I would come home empty-handed the majority of the time--not because I never got a chance to shoot anything, but because I just enjoyed being around the animals and didn't feel like shooting anything that day. It really is that simple. Sure, there is definitely a big adrenaline rush when you finally do flip off the safety or nock an arrow, but that's only a small part of the experience.
Another point is that despite the fact that humans have evolved beyond the dire need to harvest animals, our other actions have made it necessary. I don't know if you are familiar with how the fish and game set up drawings for tags, so I will summarize it in a totally inadequate little nutshell. Populations of certain animals are monitored in various regions; hundreds in Montana where I am right now. Based off of the survey of overall numbers, the number of calves/fawns/etc that year, and the number of animals the area can sufficiently support (that is another topic), the department can allocate a certain number of tags for hunters in an effort to keep the population under control. This can range from hundreds of whitetail doe tags in certain areas to single moose or mountain goat tags each year. It's a population control method that has been implemented partly because hunting is an activity quite a few people enjoy, and mostly because populations need to be kept in check or the animals will have a miserable existence (generally). I don't know if you have been in an area where the sick and starving animals move down into cities in the winter because there are too many for the area to support, but it is ridiculously depressing. I have seen coyotes literally lose all their fur in february because they are so malnourished, and deer with ribs visible at 100 yards in october. That is kind of sickening to see, and would be perpetuated if human control methods ceased.
So what it basically boils down to is a system we have implemented to try and take up the slack that human enrocachment on animal habitat has caused. Is it perfect? No, but it is almost certainly better than doing nothing at all. Hunting is something that is really enjoyable and rewarding to do, and just because everyone doesn't like it doesn't demerit it entirely. You can buy your steaks at the grocery store and I won't judge you at all for it because I can totally understand why, and I hope you would do the same for me.
And since we're putting up pictures..