The fact that you hate NASCAR is fully understood.
The fact that you try to use the Environment as another reason is, if evenly applied, probably more damning to Baseball and Football. I have heard mention by others about how many people have to go to the toilets like it is an environmental issue. Psst. I bet they would go to the bathroom somewhere if they weren't at the race.
Not even sure how many baseball games are played and by the countless number of teams, but there is a lot of fuel used getting there and snarling traffic, a lot of lights and yes, even a lot of trips to the bathrooms.
Is it wasteful? Probably yes. But no more than Baseball, Hockey, Football, etc. As here are only 36 , well, 38 cup races including the 2 non-points events in comparison to thousands of Baseball games, it pales in comparison.
As for the drivers being athletes, the training regiments of both drivers and the pit crews is grueling. A driver will lose up to 10 ponds during a 500 mile race. As far as it being a sport, by comparison everything else is just a game.