The attendance may not have been low because the public eats up the excitement of 4 high powered cars. But the real fans don't like it. The public is here today and gone tomorrow. There is no guarantee they will be back. They need to cater to the real fans.
We can debate it all we want here, the proof will be in the numbers for the promoters and the NHRA. They wouldn't keep doing it if it wasn't making sense to the bottom line.