I'm sorry, Helix, but your reply is kind of silly.
First, if there is no good or evil in nature, and if we humans are the products of nature, then there is no good or evil for us, either.
And yet we have these concepts. By your very argument, then, we are not products of nature.
As far as a dead body providing food for other organisms, that's true. However a much more abundant source of food is in plant life. That being the case, I wonder why meat-eaters ever 'evolved' in the first place?
Now about keeping a bird alive and then it would eat the worms. Ummm, I don't think so. We will feed hummingbirds through the winter and seed-eaters. But I honestly don't know anyone who puts plates of worms or meat out for the meat and bug eaters! It is the seed-eaters which are fed by bird feeders and the hummingbirds, while drinking the sugar water, get their protein from little flying things.....like mosquitoes.
In addition, it is REALLY hard for any number of birds to eat up all the worms in any given area -- birds aren't good diggers.....and worms can go a LONG way down!
In other words, if this is what you are basing your life philosophy on, you are on some awfully shaky ground, my friend!