Why don't fans give the defenders any credit at all for interceptions?

Perfect example; in last year's Superbowl Peyton put that ball right where it should have been, but Tracy Porter made a beautiful read, knew what was coming, and cut the route. And yet noone outside of New Orleans even remembers Porter's name, but everyone wants Peyton's head. This happens with every interception. To me, it's like blaming the fielders in baseball for every single hit. Why doesn't the guy who actually made the play get any credit?