In many states buying or selling wild game meat is illegal...check your fish and game regs.
I hunt (and fish) because I enjoy the challenge, and for philosophical reasons. I eat meat, which doesn't magically show up in manageable portions in the supermarket fridge. I want to source at least some of it on my own, to be involved end-to-end in the process. Butchering a carcass yourself isn't rocket science (no need to pay a butcher). Processing an animal isn't pleasant, it's messy and smelly, requires a lot of work. But that's the point, I don't want a completely sanitized view of my food. I have a new appreciation for meat now, and as a result consume less of it.
I also love being in the outdoors, and hunting is a good excuse to do more of something I love but in a very different context. Backpacking and hiking are great fun (also do these a lot), but hiking on a trail is more of an 'outsider' perspective...you are moving along a highly trafficked man made path, usually with some destination in mind. Hunting is different, fairly normal to hike 5 miles into wilderness off trail, traverse ridgelines at 10,000 ft, navigate open country, and go days without seeing another person or signs of humans. You become more like a part of the ecosystem. Often find cool little terrain features that don't show up on maps. This may be weird, but I enjoy waking up before first light and watching a mountainside for 10-12 hours. The landscape reveals itself in different ways as the light and shadows change. And you see a ton of wildlife. I've seen: bears, mountain lions, bobcats, coyotes, badgers, elk, deer, and many different birds. Sometimes I'll just sit and watch an animal for hours, or figure out what plants they're eating, follow tracks and other sign (you never see poop in the same way after you hunt), or try to figure out the daily patterns of behavior.
However, to the point of this thread, it's generally not cost effective. You don't need a truck, nor do you need expensive guns or other gear (many hunters go apeshit crazy on gear), but even if you go cheap, the cost of gas, licence, and tags will usually make it more expensive than factory meat.