Fair payment for shared wheat among three

Three housemates pool and share equally whatever they gather. One day Alice brings in $5$ bushels of wheat, Bob brings $3$, and Cory brings none. Cory pays $8 to compensate the other two for his share. If the money is divided fairly, how much more does Alice receive than Bob?

$6. Each person consumes $\tfrac83$ bushels, so Alice supplies $5-\tfrac83=\tfrac73$ to Cory and Bob only $\tfrac13$. Cory's $8 splits $7:1$, so Alice gets $7 and Bob $1.