Offerings to my God, the one that made heaven and earth, ultimately were for our sake and learning and not to give something to God per se. This is why Jesus was killed on passover and rose from the dead on the first fruits. Because it was revealed that Jesus is the lamb of God that saves from death and the first fruits from death, in other words the first to rise from the dead in the body with eternal life. It seems the basic idea behind what I would say are demons is an actual gift in a sense or the idea that there is an energy that some spiritual being actually feeds on. But God needs nothing in that sense, but does rejoice in righteousness and mercy. The material things are meant to demonstrate greater spiritual truths. That is why sacrifice is not necessary anymore, because it was only a shadow of things to come.