Conveniently, the parts that were said to be desired by the gods, thus they were destroyed by burning, were among those less desirable for humans.

The good meat was normally eaten by humans after sacrifices, not wasted.

A sacrifice was normally a loss only for the owner of the animals, if after being sacrificed in a public ceremony their remains were shared with everybody in the community, instead of being sold or consumed only in the house of the owner.

It’s a glorified, ritualized barbecue— and probably even more ethical (too bad that today it is frowned upon to see your meat before it dies)