Because lighter is better, *IF* you're going quite a ways. Accuracy is equal on that *first, cold-bore* shot, if the rifle is quality. But yeah, point taken - if you're like 90% of hunters in the east and midwest, you ain't going 100-200 yards from the pickup, most likely.
I'm moving to a rocky mountain state in just over a year, so I'm starting to focus more on light rifles. I plan to walk in a mile or 3 on occasion, to find the bigger deer, elk, sheep, etc.
I'm leaning more and more toward lighter as I get older. You just naturally get weaker, even if you work out. Which is why I went to 60 and 65 lb bows a couple years ago, instead of 70 lb bows. I hope to hit the gym more and get back to 70s, if my shoulder heals up, but until then, I can hold a 60 for much longer. When I hit my 60s or 70s (age), I'm sure I'll use a 50lb or less compound bow then, if not solely using crossbows.
I already built one ultra-light, by taking a Wby Mk 5 "Ultra Lighweight", and further customizing it (it's in .280). Now I'm considering possibly building the *ultimate* hunter for all NA big game, short of bison, yak, coastal brownies, and polar bears, by trying to get my hands on a Browning Ti short action, slapping a Proof Research 26" or 27" carbon fiber bbl on it (in .260 rem AI), and having Proof or Manners or someone build the stock I want, with some carbon fiber fill in it. It could come in under 5.5 lbs even with a 27" bbl in this config. But can't afford that at the moment. However, while dreaming here, if I make this rifle, it will be in "scout" or "pseudo-scout" config, meaning forward-mounted scope, and a stripper clip guide (but fixed mag w/floorplate; no detachables), with an actual pistol grip stock - but lightweight (not a "tactical" heavy one like from Manners). Scope would probably be the Nikon Omega / Turkey Pro / Slugmaster 1.65-5x36, but I'll have to have Nikon put in a heavy duplex reticle for me; get rid of that crap ballistic reticle in there. Probably run with Nosler Accubond LR 129s, or Nosler E-tip 120s, so I'd need about an 8.5 or 9 twist, I think.
Oh, by the way, my comments only apply if you shoot *ONLY* rested, not standing/freehand. It is certainly true that some weight helps with freehand shooting. Fact is, I NEVER shoot that way when hunting, ever. I'm always rested. I usually have a tripod. Even if I'm stalking, which I do a lot, I won't shoot until I can get over to a tree and rest my rifle against the side of a tree, and push in against it with the support hand. So, YMMV if you hunt freehand. I could see maybe wanting something a bit heavier then.
Fly weights are bare rifles under 5.5lbs. Lite weights are bare rifles under 7lbs.
Hmmm, I'd buy that if it said: "Fly weights are bare rifles under 5.5lbs. Lite weights are bare rifles under 6.5
lbs." Once you start getting up around 7 bare, I'd call them "medium-lights" or "mediums", not lights, personally... Add scope, rings, sling, ammo; it all adds up.