Jazz up the decaf

The first time I heard about decaf (on a sitcom), I assumed it was a joke. Yet, those bottled laughs weren't heard in the background. Could it be...? An American teacher later informed me that yes, there really is such a thing.

Decaf must be the most stupid invention in world history. I mean, coffee without caffeine?! That's rather like coke without cocaine. Or tobacco without nicotine. Or the Democratic Party without Barack Obama.

It lacks the active substance.