[ZeroJunk]

Do you hunt with rifles, I presume? The % lost is quite a bit lower with rifles, from what I've seen. Rifle shooters are more likely to practice than people shooting deer slugs and the (massively) better trajectory improves the range estimate margin dramatically. The difference between 75 and 100 with a rifle is irrelevant. It's the difference between hit/miss/wound with a 12ga.
I don't know anybody (though I'm sure such people exist) who practices with deer slugs on a regular basis. Everybody gets the gun out the weekend before the season, shoots a box of slugs and calls it good... if they have a scope. Iron sight guys usually don't even bother.
On top of that, most deer slugs have next to no hydrostatic shock. Most leave the muzzle well below HS speeds, say nothing of impact speeds.
We JUST got rifle hunting in our area, the first season hasn't even started for most of us, some have had a year or two. The limited numbers I've seen with rifle, the loss rate is so far zero. I'm sure it's NOT going to be zero but I wouldn't be surprised if it was under 2-4% long term, for ethical hunters anyway. There's always "shoot, hope and pray" types, regardless of weapon.

I have never hunted with slugs. I have spent more hours bow hunting than anything else. My best bucks have been taken with a muzzle loader and interestingly enough I have never lost a deer with it, plain old side lock. I have lost one deer with the bow and one with a centerfire rifle along with losing one elk with a bow. The deer with the centerfire was only about 100 yards. No excuse for making a bad shot.