What alternative did the Roman government have to turn to in order to provide support to its population?

The need to support its populace was a major factor in
causing the Punic Wars with Carthage. As the Greeks before them, the Romans had
established colonies throughout the Mediterranean to provide grain and other raw
materials to the Empire. Sicily was a major supplier of grain to the Empire. The Roman
government was expected to provide grain to those who could not afford it, and much of
this demand was met with Sicilian grain. When the Carthaginians also laid claim to
Sicily, the first Punic War erupted. The end result of that war was the withdrawal of
Carthage from Sicily. There is some argument among historians that Rome attacked
Carthage in the Third Punic War (which resulted in its destruction) in order to not only
eliminate that nation as a competitor in the Mediterranean but also to have access to
the grain fields of Northern Africa. After Carthage became a Roman province, North
Africa supplied a substantial portion of the Roman grain harvest. Its capture by the
Vandals was a substantial factor in the death knell of the
Empire.