It used to be that way.
Sadly, since the advent of KART (can't bring myself to use Crappy Auto Racing Teams' real acronym) in 1979, what used to be a great series of all (or mostly) American oval specialists from all forms of grass roots open wheel, off road, sports car, stock car and formula-car racing racing on all types of American oval tracks in front of (mostly) midwestern venues in front of large, enthusiastic crowds has disappeared forever in favor of a pallid imitation of Formula One-a-be, full of foreign rent-a-racers and club car owners who want no ovals, who have abolished invention and ingenuity in favor of no-brains spec car racing and want to cater to international fans, race exclusively on road and street courses, save for the Indy 500, and rejoice at television ratings that are about a twentieth of what they were only a decade ago.
Tony George tried to save Indycar racing in 1995 with the formation of the Indy Racing League, and for about seven years or so he had a great product. But when he invited Toyota and Honda over to compete, it was the beginning of the end, the formation of KART II, and the eventual return of the Dark Ages of Indycar.
The reason NASCAR continue to outstrip American open wheel in popularity is simple--Americans, competing in an uniquely American form of competition (oval racing), at American venues. Surely the powers that be in Indycar can't be dumb enough not to see that.
BTW, one of those durned furriners, Emerson Fittipaldi, drank freaking ORANGE JUICE, after winning the 500 in 1989. Refused the milk and drank OJ. What a p*ssy.
Some more "traditions":
Rockford--James Garner--was a fixture at Indy for years and years and years. Drove the pace car there one year as well.
US Military is always honored during the pre-race festivities at the 500. After all, it's held on Memorial Day weekend. Taps is played just before Gomer sings Back Home Again in Indiana. And when Gomer sings, there's not a dry eye in the House, I can assure you. Having been to the 500 on a number of occasions, it puts a lump in your throat every time.
If Indiana is in the hunt in the NBA playoffs, the pre-race invocation usually ends with, "and May the Pacers Win Tonight."
Many **28** show up at the 500 for the race and the 500 Festival Parade the day before.
It's very hard, the first time you see it in person, to stand for the three-wide start without your knees and hands shaking. It's a very emotional and nerve-wracking experience. I can't imagine what it must be like for a rookie driver to experience that.