If you want to know why NASCAR will miss Tony Stewart after he retires as a driver at the end of the year, Stewart showed us Friday night.

The three-time NASCAR Sprint Cup Series champion was in Tulsa for the Chili Bowl Nationals, the first big dirt race of the season and a hugely popular event. Stewart, who grew up racing midgets, is a two-time Chili Bowl winner, and he volunteers his time at the event driving the tractor to get the racing surface packed exactly how the racers like it.

Friday night at the Chili Bowl, Stewart went up in the grandstands to confront someone who heckled him and, according to reports, gave Stewart the one-finger salute. The two had a confrontation that lasted maybe 25 seconds. Stewart got up in the face of the heckler and told him exactly what he thought, as fans yelled their encouragement. No punches were thrown, although a security guard pushed the fan back in his seat.

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It was yet another reminder that Stewart says and does whatever is on his mind, which is a very good thing indeed. I would submit that NASCAR would be a whole lot more interesting if drivers spent more time speaking their minds than thanking the boys back at the shop for working so hard.

Over the years, I've seen Stewart get into it with other drivers, reporters and NASCAR officials. He's railed at dumb rules and policies, and heaven help you if you block him on the track. Stewart is wrong sometimes, but you always know where you stand with him. He'll look you in the eye and tell you exactly what he's thinking, which is a good thing.

And I'll say this, too: Some fans think a race ticket --€” or an anonymous social-media account --€” is a license to spew venomous and hateful words with no consequences. Race tickets aren't, nor are Twitter or Facebook accounts.

That's a lesson some people need to learn.

And Professor Stewart had class in session Friday night, and I say, good for him.