Because they were both American high schools. If they had been playing a school from Mexico it would be a different story. Please tell me you're not serious with that question.
Where I live on the fith of may there are Mexican flags everywhere since it's a Mexican holiday. Local businesses even put them up. I don't feel offended by that as long as they aren't putting them above American flags or are using it to demean the United States. It's just a symbol of ethnic pride. (or in the case here, an excuse to get drunk) I don't think he gets that.
He must have a shitfit on St. Patties day.
By your dumbass logic to high schools in a basketball game equals a US vs Mexico sporting event. Seriously, either re-watch the video or stop posting crap that makes you look like a fool.