What is the importance for the Roman Republic to conquer territories in the Western Mediterranean?

Conquest in Western Mediterranean had a devastating nature for the Roman Republic.
Miscellaneous population has grown. In the provinces flourished treasury
Without the support of all Italy, the Roman republic would never have won the Punic Wars and did not join the territory of the Western Mediterranean, but all the conquered trophies received only Rome, since the rest were not Roman citizens. Allies demanded equal rights with Rome.
In Rome itself, there was a bundle of society on super-rich and impoverished. To know also divided into reformers and opponents of change. It pushed the Roman Republic to the Civil War.