Most likely they only have one loot call used for all creatures in the game. So you would have to hunt even more large creatures to hit the 95% or whatever balance they have that is seen on the smaller mobs. Hence why everyone tells all the new players to hunt at or below their levels as they don't have the Ped to cycle to get to the mid point, they either loose or they either win more then that. Seeing as a ton of kills are in the loosing category you would have to hunt a large creature a ton to hit the same return percentage as a small creature not counting markup on stuff.
It would make more sense if they created several different loot calls for level ranges of creatures such that higher level creatures would have less of a loss on the low end but globals and hofs on them would be nerfed as well to make up for it. That way players wouldn't have such a ruff time moving up the mob ladder and loosing a ton of ped on one bad hunt that they couldn't make back up the next few. It would be nice if they at least did this with "Boss" or "Event" monsters that the company spawns or players summon, since it takes an incredibly long time to hit the middle ground that the company has aimed for in loot returns to players (96-98%?). At least at this time. Its not like you can summon the creatures and hunt 10k of them to hit that return ratio, granted the markup on the items would be sky high to start with but the losses to start with could also cause people to never come back to them again so the design time that went into the creatures would turn to be pointless until the player base grew enough to summon them faster if they ever could.
You could also in theory bind different loot calls to change depending on how much of that creature was hunted with more stable calls given to lower hunted amount of creatures so it became a risk and reward function. You could risk hunting something everyone was hunting for larger percentage returns, but you would have to hunt it more times to have the chance to get the large return. Or you could hunt something that no one was hunting, but while you might not get the hof and have a hard time getting a decent global you might be able to walk away with some decent mark up items.