I absolutely hate salary systems that give an advantage to people who are pushy, jerky, entitled, or privileged. Some of the best developers I know are pleasant, friendly, modest, don't like confrontation, and pay more attention to the work and the team than how much they're pocketing. Those people shouldn't be paid less.
Learn to defend your work and ask for what you deserve.
But knowing what you deserve is a complicated art that involves measuring yourself against your coworkers and your industry, and having a good working knowledge of the current market. For the people who don't know what they want, some of them are going to err on the side of asking for too little, and some will ask for too much. I would much rather spend my time bringing the shy up than battering the arrogant down to something reasonable.