Interesting insights from some of the world’s biggest advertisers on their view of the value of Facebook Ads.

Marketers From GNC to P&G Weigh in on Social-Platform Strategy

One in five clicks in the U.S. happens on Facebook, and like any mass platform, most brands maintain a presence there and carefully cultivate their fan base.

But do they need to advertise as well? That’s the question facing brands — as well as investors –as Facebook prepares for its anticipated $100 billion IPO on Friday.

The Facebook ideal goes something like this: a brand builds a presence there and cultivates a fan base. That fan base spreads the word about the product. When brands want more impact, or to reach non-fans, they advertise.

But the reality is that much of what brands spend on Facebook isn’t going into its coffers. A Facebook presence is must-have for brands. Facebook advertising, on the other hand, is not. General Motors showed that by telling the Wall Street Journal earlier this week that it’s pulling the plug on all Facebook advertising — $10 million of it — even as it spends another $30 million building and maintaining a Facebook presence for its various car makes and models.

GM’s move puts it very much in the minority. Most brands with big presences on Facebook are also spending significantly on advertising. But it’s clear that Facebook still faces steep hurdles in getting marketers to increase their investment to grow the $3.15 billion they spent on the network in 2012.

“I think brands are still trying to get their arms around what Facebook means to them. Is it a click play? Is it an exposure or impression play? Will it be measured in digital GRPs?” said Chris Copeland, CEO of WPP’s GroupM Next. “There are still a lot of unknowns.”

Kantar Media Compete measured the effectiveness of Facebook ads in automotive, travel, tech and retail as defined by whether the user clicks on an ad, visits a brand page, or seeks out more content about the brand.

GM doesn’t particularly need Facebook to build awareness. As the nation’s third-largest advertiser, it has plenty of ways to reach consumers, and even send them to their Facebook page. But the timing and absolute nature of GM’s statement on Facebook reverberated through the industry.

“Blaming Facebook for a lack of ROI on your advertising is akin to blaming the internet because no one purchased from your website,” Brian Wallace, VP-strategic marketing for Samsung Mobile. “Facebook is a platform that attracts close to a billion people and it’s ultimately up to advertisers to understand how to optimize this platform for your customers.”

Mr. Wallace, who responded to an Ad Age query while en route to a meeting at Facebook headquarters, said Samsung spends twice as much on maintaining its Facebook presence as it does on advertising. What would make Samsung spend more? More data in return, Mr. Wallace said. “They keep their data too close. This is the only thing preventing me from investing more in their platform,” he said.

Advertisers keep their strategies and spending levels close to the vest, but in conversations with Ad Age one theme emerged: most major consumer marketers are spending both on Facebook as well as Facebook advertising. But the paid advertising on Facebook is under pressure from other channels that can do the same thing, just cheaper.

Supplement retailer GNC said its spending on Facebook is likely to stay flat or increase just slightly in the near term. Meanwhile, its investment in content will rise significantly. CMO Jeff Hennion said it’s more cost-effective to drive people there via email, direct mail, or even TV ads that show a link to the Facebook fan page.