But we like to be able to set our own moral standards, and the point of Genesis 3 onwards is that when we try to do that we mess things up.
And yet the moral standard we're given alongside Genesis is overly simplistic, lacking in key areas and just flat out unsupportable in others; the calibration of relative infractions is woeful, with issues regarding haircuts deemed at some point to be an egregious matter whilst rape and slavery are never decried.
The reality is we need God to tell us what is right and wrong.
The reality is that people choose the god, and the denomination of that god, which fits the morality they're comfortable with, and the source materials are so loosely written and even more loosely translated that if they look far enough they can probably find one that fits; if they can't, they just go all John Smith on it and write their own.
We have the choice to accept it straight off or learn it the hard way.
Except that if you read a different book we have innumerable chances to get it right, going round and round in spiritual reincarnating circles until we achieve it and get to step off the hamster wheel; or we have one chance to achieve glory and be taken to Valhalla; or we have one chance to get it right and be weighed against Ma'at's feather by Anubis...
Adam realised he was naked and unable to cover himself properly. This realisation was an outward manifestation of inward shame, and he couldn't deal with either of them himself.
So Adam was, purportedly, created without a sense of what? Notwithstanding that the Judao-Christian attitude regarding nudity and sexuality - particularly female nudity and sexuality - has been more of a hindrance on morality than a benefit, why SHOULD Adam feel shame at his nudity?
The outward shame required a blood sacrifice to provide a covering (an animal skin), and the inward shame and estrangement from God could only be dealt with by someone being tempted and not yielding to that temptation, on Adam's behalf, though it resulted in his murder by the same people he came to save.
Adam covered his nudity with leaves; it wasn't until he was thrown out of the Garden into a less temperate locale that a more robust clothing was required. Even then there isn't a need for a sacrifice, you can make a jacket out of the skin of an animal that's died of natural causes.
Just trying to answer your original question of why God requires a blood sacrifice.
You're raising practical reasons why killing might have become necessary for human livelihoods, fair enough, but that doesn't explain why God's forgiveness required a human sacrifice - or, indeed, any sacrifice at all - nor why we need God's forgiveness for something we've not done and arguably wasn't the responsibility of Adam even if he did do it.
O.