Doesn't matter whether it's mindless or not. Consumption is consumption. Educating yourself by reading programming articles could be considered an investment, which is the distinction you want to make here, but if it's not an investment towards future production, then it's still just consumption and not much different from playing Farmville.
I still don't agree. I don't think knowledge for the sake of knowledge is such a bad thing. I feel happier when I learn things, even if the things are unlikely to help me be productive in any measurable capacity. I will go on Wikipedia binges on bizarre topics like fighter aircraft or quantum mechanics, and it makes me happy even though I certainly don't retain any real expertise of the subjects. I guess that makes it "entertainment" more than anything, but I think that's fine.
No one said consumption is "bad". All that's said is that consumption is dependent on "production", and "production" gets its value from "consumption" (even the producer ends up being the only consumer).
That wonderful book you read? It wasn't created by someone reading; it was created by someone writing. If everyone read Wikipedia and no one wrote Wikipedia, there wouldn't be anything to read.