You're correct as far as the numbers go. But as I'm sure you're aware of, a 2002 dollar is now worth 55 cents. The way things are going, NHRA may resort to handing out gift cards to the winners and it might not be long before my little used car dealership will be able to assume the role of NHRA's title sponsor.
It's a shame. We all know that NHRA can't match NASCAR's purses and why it can't. But what they pay the pros now won't even cover the expense of getting a top flight pro team and all its equipment to the track and back, let alone actually start the car and make a pass. It's getting to the point to where the only way to survive nitro racing without sponsorship is to run a total shadetree operation and count on R1 loser money.
NASCAR poor-boys used to and may still do this all the time. Get qualified 40th, drop out on Lap 1 with an "unknown vibration"

and take home last place money which averages around $100,000. Do that for a season and you can bank some pretty good coin with relatively little expense.