Famous 2010 Old Spice Super Bowl ad, starring Isaiah Mustafa. (AP Photo/Procter & Gamble Co.)

Once upon a time, major advertisers happily coughed up what was then considered to be a vast sum of money for Super Bowl ad time. They were comfortable in the knowledge that the ad would be seen by tens of millions of people and result in zillions of extra thingamabobs being sold. It was simple. It was effective. It was like printing money.

But this year, CBS is charging $3.8 million to $4 million for a 30-second commercial during Sunday’s Ravens vs. 49ers game.

That’s up a minimum of $300,000 from 2012, when, yes, your ad was part of TV history’s most-watched broadcast (111.4 million viewers on average) — but you shelled out a whopping $3.5 million for the privilege.

This year’s price tag also is nearly $1 million stiffer than a Super Bowl as recent as 2009, when a mere $2.9 million bought you an average audience of about 106 million.

That was the year Bud Light gave us Conan O’Brien getting talked into doing a Swedish TV ad and such duds as a guy blue-skying about Doritos-flavored beer.

Back in 1984 — the year of Apple’s Ridley Scott-directed Orwellian MacIntosh ad — regarded as the best Super Bowl ad ever and maybe the best ad, period — 30 seconds’ worth of Super Bowl time cost about $370,000, according to Nielsen — for which you got nearly 78 million viewers. In today’s dollars, that ad time cost less than $1 mill.

View Photo Gallery: From “Mean Joe” Greene downing a Coke to the ETrade baby: A look back at the most successful Super Bowl ads.

With the cost of a game-day ad being what it is, and ad clutter infecting this sacred TV franchise (approaching 50 minutes), two schools of advertisers have emerged: those who preview their ads before kickoff to amortize the cost over social media and those who think such spoilers blunt a Super Bowl ad’s impact.

For this year’s Super Bowl XLVII, more advertisers put out some, or all, of their ads ahead of time — on movie screens, online and across social media.

In some cases — as with Audi, which is making its sixth Super Bowl appearance — companies produced multiple ad endings and have asked viewers to vote for which they’d most like to see Sunday. Audi thinks this is the only way to go, its research showing that chatter about Super Bowl ads begins a quick fade within 24 hours of the game.

Launching the ad before the game lets the company have “a much longer conversation” with consumers, Audi’s brand-marketing general manager told Ad Age last month.

“The value is certainly in the anticipation of the Super Bowl,” Loren Angelo explained.

Releasing your ad early also comes with fringe benefits.

On Wednesday night, CBS — this year’s Super Bowl host — aired a TV special: “Super Bowl’s Greatest Commercials.” It purported to list the 10 best Super Bowl ads of all time — but included looks at the making of Budweiser’s newest Super Bowl ad with Clydesdales and a look at the making of Toyota’s new ad for the RAV4, featuring “Big Bang Theory’s” Kaley Cuoco as a wish-fulfilling genie.

“I can’t believe it — I am so excited,” Cuoco said on the special. She also praised the ad creators for letting her be “sarcastic and funny,” which is “kind of my thing.”

Nearly 10 million people watched that on-air valentine to Bud’s and Toyota’s ads — the second-biggest audience on TV that night, behind only Fox’s “American Idol.”

The TV special’s list lacked Apple’s “1984” ad, as well as lizards Louie and Frank, who starred in one of Budweiser’s longest-running and most successful Super Bowl ad campaigns. Also missing: Old Spice Man, a.k.a. former NFL practice-squad wide receiver Isaiah Mustafa, whose 2010 Super Bowl ad was viewed on YouTube more than 13 million times by July of that year, spawning a social-media blitz that NBC News said “changed the rules of social network marketing.”

Other advertisers say that all this spoiling of Super Bowl ads will wind up killing the golden-egg-laying goose.

“I’m more of the old school; I like the element of surprise. If I ruled the world, I’d go back to holding out and waiting,” John Norman, chief creative officer at TBWA/Chiat/Day Los Angeles, told the New York Times this week.

That element of surprise can really work for an advertiser — particularly if all the other advertisers in their category joined the spoiler stampede. This year, for instance, almost all automakers who’d bought time in the game released at least portions of their ads ahead of Sunday’s game — except for Chrysler. Chrysler’s ad is one of this year’s most highly anticipated, what with last year’s Chrysler ad — also held until game day — winding up being the most memorable ad of that Super Bowl. It featured Clint Eastwood telling viewers it was “halftime in America” and urging people hurt by the economy to “make a comeback” because “our second half is about to begin.”