How that gravel taste? how you paid your medical bills?
He’s adding on from the previous line. He’s asking the “regular niggas” how the gravel tastes. Meaning he is asking how it feels to be lower(gravel meaning on the floor, implying he is higher) on the economical scale (Hence he has the money to pay for his medical bills and “regular niggas” don’t). Also notice how “gravel” and “gavel” from the previous line sound the same.
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