Haha I did that at a Bison game a couple seasons ago! I wore a green sweatshirt with SIOUX STRENGTH written really big on it. NDSU's record was less than stellar at that time, and UND was doing pretty good...
Incident #1: Some old lady in front of concessions came up in my face and started talking crap. I laughed in her face and didn't pay attention to anything she said.
Incident #2: As I was walking up the stairs to get back to my seat, a group of (actually pretty cute) guys yelled out "Sioux suck!" My response was (quite loudly) "Wait a sec, what's your record this year? And what's our record this year?" Nobody around me said anything back to that, so I kept walking
Not sure which away games I'll make it to this year, but FIGHTING SIOUX all the way baby!!!
(Edit) I am actually a Bison fan too... but a Sioux fan first