When the only thing you have to say about your product is what is doesn't contain, you have a marketing problem:
Scene: (Guys singing a drinking song in squeaky high-pitched voices and swilling fictional "Beck's with Helium.")
Voiceover: We could have put strange things in our beer, but we didn't.
High-pitched voices are hilarious to people over the age of 21, no question about that. But this is an interesting concept; the idea of stuff your product doesn't have. Why haven't other companies used this in their commercials?
Apple: We could have put minced garlic inside our iPod Nanos, but we didn't.
Ford: We could have made our pick-ups out of styrofoam, but we didn't.
Coca-Cola: We could have called our cola "Pepsi," but we didn't.
GE: We could have made watchable commercials, but we didn't.
Voiceover: Beck's -- choosing to use only 4 all-natural ingredients for over 125 years.
Nice. It's a good thing they put this in their ad, because Beck's is the only do-gooder who uses natural ingredients. Hey Budweiser! PWNED! Beck's is on to your little game and all that chemical waste you pump into your beers! You hillbillies probably use something disgusting like, uh, chicken hearts or something in your beer! Nasty, dude, just nas - wait, I'm being told there's not actually any chicken hearts, or for that matter, any artificial ingredients involved in Budweiser. Well, try doing it for 125 years, assholes!.... oooohhhh, shit... It's apparently been 131.
Well, how about fellow European brewer Heineken? What's in your beer, you big fakers. You nerdy Dutch chemists with your genetically-modified tulips and your -- oh, wait, what? You're using water, malted barley, hops and yeast to brew your beer? Well, whatever, Beck's only uses FOUR, dude! Four ingredi - oh wait, that is only four ingredients....
I wonder how the Beer Drinker demographic crosses over into the All-Natural Foods demographic, anyway.
The lesson here is not to advertise your product by what it isn't. The title of this post refers to an old adage from Ye Olde Ad Man David Ogilvy that you should avoid using negatives in your ads (his book used to be obligatory reading material in college marketing classes.) The danger is that the consumer could miss the negative altogether -- in Ogilvy's example, if you're a salt company and your headline is "Our salt contains no arsenic," people perusing a magazine or flipping through channels could read it as "This salt contains arsenic." And in Ogilvy's time, you got a lot more of the consumer's attention, because there was a lot less advertising out there.
Just think about what you're competing with now -- talking about what your product isn't will confuse people when you've only got a tiny fraction of their attention. Best case scenario, your consumers will get a little laugh. Worst case, your audience will think you're selling something you're not.
Now why can't I find that new Beck's with Helium at the liquor store...