If any modern celebrity was sporting Dallas Cowboys gear in the real world, we'd probably roll our eyes and shake our fist in apathy. "Jeez, man," we might say, "how much more obvious can you be?"
But frankly, I'm giving a pass to Pink Floyd's David Gilmour, seen below sporting a Cowboys T-shirt while, according to @HistoricalPics, he takes in a Led Zeppelin concert with Paul and Linda McCartney, circa 1975.
No. 1, Pink Floyd is one of my favorite bands of all time, so Gilmour can do just about anything he wants and I'd be cool with it.
No. 2, the Cowboys weren't America's team back then. Yes, under the leadership of coach Tom Landry, the Cowboys won double-digit games every year but two from 1966-81, but when this photo was snapped, the team wasn't THAT far removed from going 18-46-4 during its first five seasons in existence from 1960-64. So, it couldn't have been that trendy at the time for Gilmour, an Englishman, to be wearing such a shirt (though, strangely, The Who drummer Keith Moon also had been photographed wearing that shirt).
One other thing, after further research, it appears this photo might have been snapped at the Knebworth Festival in 1976 while the trio watched the Rolling Stones (and not Zeppelin).
So, while we don't know who or when Gilmour, McCartney and McCartney were watching at this moment and while we don't know what they were smoking, we do know this:
David Gilmour is wearing a Dallas Cowboys T-shirt. And it looks just fine.