Just another scheme of how the richer get richer.

So even if they were not tax exempt, they wouldn't have to pay taxes anyway.

Most of the actual profits fall under NFL Ventures, which is not tax exempt. They pay taxes.
Team owners also make a lot of the money the NFL makes, and they pay taxes.

I don't buy it. It's an accounting trick.

They would have made $28 million in profit if they paid their Commissioner only $1 million a year instead of the current $29 million. If they are so poor why are they paying their Commissioner such excessive amounts?

Since Roger Go0dells salary is more than that, then the NFL is not paying his salary (or at least paying the majority of it).

Its likely that NFL ventures (which is for profit, and pays taxes) is paying roger Go0dells salary. In fact, (2011) the NFL claims that it made 4 million, and had expenses of about 9 million. Yes, this sounds low, but the majority of the money goes to team owners and NFL ventures, which is not for profit. Don't believe me, search for the NFL's form 990. You can find it pretty easily at the IRS.