Garbage to the ragpickers of Seemapuri is like gold to them .Explain

Rag picking is the means of survival for the ragpickers. According to the author, it is their "daily bread, a roof over their heads, even if it is a leaking roof". Thus, it is equivalent to gold for them. Besides, for the children it is "wrapped in wonder" for they, at times, chance upon "a rupee, even a ten-rupee note"