Because we are usually mortal, that is, non-awakened. Therefore, if we can't find out the reason for some phenomena and guess according to our own emotions, it will be endless, but must we guess? I'm afraid not, otherwise we are all gods and don't need to practice.
So for "giving food", many people on the Internet pay attention to "dreams", but it is hard to say what dreams must mean. Clinging to dreams, or treating dreams as an inducement of devotion, is probably not the fundamental interest of learning. Therefore, if you run your own "giving", you will have substantial benefits as long as you try to be as good as you are, including accurate behavior and correct intentions. This benefit cannot be explained by dreams. Of course, I'm not saying that all dreams are meaningless, but that we "can't grasp" to interpret them. "Legal guarantee" is to make food to the extreme. ...