Ezra Klein has a working theory for why Mitt Romney's (intended) presentation of his proposed Economic Plan in Detroit the other day played to an empty stadium:

Romney is very clear: Nothing is going to change for anyone anytime soon. Romney is less clear about what will change in the future: His Medicare plan still omits any information on how fast his vouchers will grow, which means we can’t say how much money his plan will save, or what it will mean for tomorrow’s seniors. But put that aside for a minute. We have enough detail to say that Romney’s cuts in the next 10 years have to come from outside Social Security and Medicare. ...
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... He’ll “send Medicaid back to the states and cap that program’s rate of growth,” and then “do the same for other programs, like food stamps, housing subsidies and job training.”

Sending the programs back to the states is a red herring. The key bit for deficit reduction is capping their rates of growth. Which is to say, cutting their rates of growth. Which is to say, cutting them.

What Romney is essentially proposing to do is finance a massive tax cut by cutting Medicaid, food stamps, housing subsidies and job training. In other words, the neediest Americans — and, to a lesser degree, federal workers — will be financing a massive tax cut.

Romney got more jeers from the media for the terrible optics of the putative Republican nominee for President giving a major campaign speech in an almost empty stadium, than he did for the substance of the speech, which obviously is appalling. And to be fair, as Benjy Sarlin notes, the huge Ford Field Stadium was not the original location for the speech:

Mitt Romney’s big speech in Michigan Friday was delivered before a crowd that organizers pegged at roughly 1,200.

Apparently the seats had sold out so fast that the campaign had been obliged to shift from its initial venue to a larger space. The site they found was the enormous Ford Field Stadium. The problem: it seats 65,000 people. So early-on the campaign was faced with the issue of how to make it look like he wasn’t addressing a near-empty arena.

Their solution was to set up the seats in the middle of the field. However, despite those efforts, a live feed of the event clearly showed tens of thousands of unfilled seats and Romney’s speech had an audible echo as his voice bounced around the cavernous space.

On the other hand, presumably Romney knew how 1,200 people in a stadium that seats 65,000 would look.

Then again, that kind of cluelessness is certainly consistent with the political savviness of a man who makes $10,000 bets with his opponents in a primary debate, declares that he is not concerned about the poor, trashes a government bailout of the auto industry that saved thousands of jobs, in the state where those jobs were saved, and tries to curry favor with ordinary Americans in the worst economic crisis since the Great Depression by telling them he and his wife own only American-made cars -- four of them, including Ann's two Cadillacs.