That's just it - those other nations have lobbyists who pay for political favors, too. But they also have widespread corruption among civil servants at all levels. Thing is, their front-line civil servants are poorly paid, and are effectively forced to accept bribes to pay for food, shelter, and clothing. When those already-corrupted civil servants are promoted, the corruption moves up the ladder with them. And for all the bad press Duterte got (much of it rightfully), he pushed for higher wages for the civil servants and attacked the corruption. Their corruption is still much worse than our own, but it's not as bad as it was before Duterte.