The point of earmarks was to bribe lawmakers into ignoring the substantive policies in the bill they were debating.
Two years ago, House Speaker John Boehner explained to a reporter why he was having trouble passing a highway bill.
"When it comes to things like the (last long-term) highway bill, which used to be very bipartisan, you have to understand it was greased to be bipartisan with 6,371 earmarks," Boehner told reporters. "You take the earmarks away, and guess what? All of a sudden people are beginning to look at the real policy behind it."
To repeat, without earmarks, lawmakers actually consider a bill's underlying policy.
This points to the last remaining argument for earmarks. (The recent leveling off in appropriations has, in my opinion, showed that banning earmarks actually reduces federal spending.)
From an elitist viewpoint (and I use that term neutrally), it was a good thing for the executive and congressional leaders to distract rank-and-file members from the substance of the policy being voted on. If you view the average congressman as too dumb, too busy, too uninformed, or too ideological, then you're probably happy letting the likes of Boehner, Nancy Pelosi, and the White House legislative affairs office bang out a deal and then trick their members into supporting it.
If, on the other hand, you are still attached to the idea of a representative democracy, then you like the ban on earmarks, and the phenomenon of congressmen voting for or against a bill because of the policies it would put it place.