According to the song, the humps of garbage were their wealth. These were what gave them power in the middle of the surrounding stench of all kinds of pollution; that beyond a “garbage” society (metaphorically), these cities/communities endured, lived, survived and strived with simple happiness and dignified values as to honesty, respect, and hope in rescue or salvation like seeing a single bird.   
Abusive human activities greatly affects Mother Nature. The fact that we, humans, who are the stewards on this planet and are the sole beneficiaries of nature, are the ones who destroyed the gifts which Mother Nature has offered us.    
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