We choose repatition because throughout the speech anthony keeps on saying how the people in the croad are his friends and they need to trust him.
moreover, he hath left you all his walks, his private arbors and new- planted orchards,(crowd cheers) on this side triber; he hath left them you.
Good friends, sweet friends, let me not stir you up to such a sudden flood of mutiny.
Antony's use of repetition in his speech is incredibly effective because he is addressing a mod of lower class people. This enforces his point to a crowd a of people who do not have much, if any, education. He uses repetition to drive the crowd into a riotous fever against the Noblemen who killed Caesar.