Because the case wasn't decided on the basis that it was Malone's dwelling... In fact, I don't believe the word even appears in the opinion.
Uh, the first sentence includes "standing on the front porch of his home."
http://www.in.gov/judiciary/opinions/pdf/03200808jsk.pdf
The case focuses more on how to establish "officer safety" - basically articulable facts that an officer can state that caused him to be concerned. But, it does necessarily go into whether having a gun on one's porch is sufficient under Terry.