You talking about programs with the most cascade processors? If it's getting denied through 2-3 processors and then accepted by the last, well then that last merchant/processor account won't be around for long. There is a reason why it was declined through the first couple processors.
However, I'm sure their conversions are higher. As our possibly the programs running their own merchant accounts with less restrictions, they might have a higher c/b ratio but are able to eat the costs because of their size.