By now you know Facebook just spent $1 billion to buy Instagram, the social photosharing app on the iPhone and recently added to Android.

If not, just Google it. 

The pundits are buzzing about the news and speculating on the various ways it helps Facebook, a soon-to-be public company. But as far as I’m concerned, there’s only one reason Facebook wrote such a big check for what’s tantamount to a fancier Flickr …

They did it for the kids.

Facebook has an age requirement for membership set at 13 years old. While they don’t really verify age, it serves as an alert for parents and remains a solid filter for keeping out the youngest among us. Instragram, by contrast, has no such requirement. If you have an iPhone (or the popular-with-kids iPod Touch) or Android phone, you can share pics, no matter your age.

As a result, Instragram is huge with tweens and teens. As one mother points out in Business Insider, “… these kids are crazy about Instagram, it is a dominant form of communication for them. And, these kids (affluent, Chicago suburbanites) don’t have Facebook accounts yet and won’t for 4 or 5 years - if I were Facebook this would concern me. A whole bunch of kids running around who may decide they don’t need Facebook.”

Facebook was once the upstart - which wasn’t that long ago - and has a vested interested in stamping out “the next Facebook.” That’s what this acquisition did.

Look, I don’t doubt Instagram will bring some great tech and brainpower to Facebook, but that isn’t worth a billion bucks. This was much more about the threat than the opportunity.