The NT is full of sacrificial language.
Some scholars suspect the predictions as having being later inventions.
I also believe that the words of institution are likely to be among the most carefully preserved of Jesus' words. Interesting enough, there is no definitive theory among Christian theologians as to why Jesus died or how his death saves us. That's surprising when you consider the amount of ink used on other topics. My personal view is that this begins to get into areas that we can't know. We know what God has done for us, but we don't know what alternative were available and why he chose to do things the way he did.