FORTUNE — In the space of a week General Motors Co. shook the global advertising industry — twice. First, it announced it was halting paid ads on social network Facebook, a still emerging advertising platform. A few days later, the car company said it was also passing on televised commercials for next year’s Super Bowl, a bastion of high-spectacle, high-machismo automotive advertising. What in heaven’s name is going on in Detroit?
The straightforward explanation is that GM’s (GM) new head of global marketing, Joel Ewanick, is looking for ways to trim the automaker’s estimated $4.7 billion global annual advertising budget — the largest in the world. GM shares are selling at about two-thirds the price of its November 2010 IPO, in part due to financial losses in Europe and partly because the restructured company hasn’t yet proven that its earnings are sustainable.
In 2011 GM earned $6.1 billion in net income, an amount enlarged by a special exemption from income tax granted by the U.S. government, which owns roughly 25% of the automaker. That compared with $20.2 billion in net income by Ford Motor Co. (F) and $19.7 billion by Volkwagen AG. GM, while solidly profitable, trails the other top six global automakers in terms of gross profit margin.
“I’m not sure all of this will move the needle with the financial community,” said Michelle Krebs, a senior analyst for Edmunds.com. “What GM really needs is better sales and profits. I don’t really see the bigger plan for how to do that.” In particular, Krebs questions the decision to drop the Super Bowl in a year when GM will be introducing its new line of Silverado and Sierra pickup trucks, as well as large sport-utility vehicles based on those pickup architectures.
Ewanick, who first made his mark with Hyundai before coming to GM, told The Wall Street Journal he thinks the Super Bowl remained effective, though he didn’t intend to buy time for the championship every year. A 30-second spot this year cost $3.5 million; next year the same spot will go for $3.8 million. Typically, multiple automakers buy advertising for the broadcast, and the commercials usually are specially produced and circulate widely on the Internet even before the game.
The move was particularly surprising, since one of the most aggressive automotive advertisers at the Super Bowl remains Hyundai, Ewanick’s former employer. The top marketing post at the U.S. subsidiary of the Korean company is occupied by Steven Shannon, a former GM marketing executive. (Shannon seemed only too pleased to tell the Automotive News, that the Super Bowl is a “perfect venue” for Hyundai, lauding the game the as “most watched” show in the U.S.)
CBS, broadcaster of 2013 championship, surely realizes that GM will be in high marketing mode for its new full-size pickup trucks later this year, which may help to explain why the network has priced the game aggressively. GM’s Silverado and Sierra furnish a disproportionate share of profit in the U.S., the automaker’s most important market. Hyundai doesn’t build full-size pickups.
GM’s decision to drop paid Facebook advertising, which the automaker said was revealed inadvertently two days before Facebook’s initial public offering of stock, was an easier call to make and not as critical as cutting back on the Super Bowl. GM of course can resume Facebook paid ads whenever it wants and doesn’t have to fight for limited inventory, as it does during a television extravaganza.