The reason why is because the denotative definition is "a place where you live, reside" which is the literal definition of "home". This is the definition you'd find in the dictionary. Whereas the definition of "warmth, comfort and affection" is an emotional connection often placed on the word "home".
Answer: Symbolism takes something that is usually concrete and associates or affixes it to something else in order to give it a new and more significant meaning.
