Many systems that work perfectly well can still be exploited. Besides, gaining a Triumph in the Roman republic wasn't that difficult. Many times they were rewarded to a consul for simply quelling a minor rebellion of a restless Italian tribe. Only once the Senate started to fear the growing power of individual generals did they start handing them out more sparingly considering that a triumph was basically the biggest public relations ploy and popularity gaining tool available to a Roman politician. The mob loves a good parade. :)