Oh, that's why...
We build big loud trucks whose only purpose is to jump really high into the air and crush cars and make noise. I donned no sleeves on this frigid Friday in February (because you shouldn't wear sleeves to monster truck rallies, duh) and watched as trucks with names like "El Toro Loco," "Monster Mutt," "Superman," and "Grave Digger" revved their engines, jumped over cars and, in some cases wrecked themselves from jumping too high and landing on one wheel. The whole thing was totally ridiculous and is probably on the list of things that proves that our collective IQ is rapidly lowering (possibly from breathing in too many monster truck fumes). I know I killed a few brain cells that night, and it wasn't from alcohol.
The show consisted of a bunch of different events crammed together with no particular reasoning as far as we could tell. For instance, they started out by "racing" the monster trucks around the track with two jumps per lap, but I still am not sure exactly how the winner was chosen or why. It seemed to be which ever truck crossed the finish line first, but if I wanted to see things go fast, I would have gone to Nascar without my sleeves! I was rooting for the car that hit the jumps most recklessly! There were some ATV races mixed in there too which, after seeing the monster trucks race, looked like a bunch of Hot Wheels toys driving in circles. That was followed by a ten minute set up for what we found out was snow mobile jumping (the actual performance lasted about as long as the set up and ensuing take down of their ramp). Oh, did I mention that this did not take place on snow? Then, thinking that we couldn't get any more confused about what was happening, there was a 12 minute (at least) dub step laser light show. Still not sure why.
The end of the show was what we all came to see, the monster trucks ran all over the place, crushing cars and driving up the huge ramp in the middle. Two trucks broke something, which was AWESOME, and they all made a lot of noise and got into the air a few times. Still doesn't get the testosterone pumping like a fighter jet fly over, but it wasn't bad. AMERICA!