Please explain this quote from A Scanner Darkly....
 

From PKD's masterpiece:

My first observation is that the quote is lacking its context: having read the book many years ago, I cannot now say anything for certain without first finding that quote and reminding myself about it.

However, my guess would be that it would represent Dick's ironic take on a drugged-up character (Bob Arctor or one of his doper buddies) who thought he was being profound but was in fact talking outside of our expected logical constraints and was in fact simply voicing paradoxical &/or absurd notions that do not bear detailed analysis.

If you like analysis there is something on the book at the following site:

http://www.philipkdickfans.com/frank/encounte.htm
http://www.philipkdickfans.com/frank/scanner1.htm

I just read the book last month. I think it is part of his drugged out psyche. But, I also think it had to do with a sentiment against big corporations that are everywhere in our lives.

In addition to this quote where he seems to bash McDonalds, he also bashes Coca-Cola a lot throughout the book. I think he had an inate mistrust of big businesses.

How does he bash McD though? What does he mean by not going outside?

I've never read the novel or any Dick's work, but I will take a stab (put my BA in English to use):

I think what he is saying, that all of this 'stuff', these images and products that inundate our lives are becoming part of our consciousness, THEY ARE EVERYWHERE, and someday without every leaving our homes/lives, their ubiquitity will essentially become part of us.