The fact that Goodell makes $30M per year to screw up the game is the scary part.
The NFL is simply a trade association. The only money the NFL makes are membership dues from the 32 teams, income from it's investments and fines. I don't have current numbers, but in 2010 this amounted to:
Membership dues: $183,789,138
Investment income: $270,439
Fines: $ 240,000
BTW...the NFL lost $42mil in 2009 and $52mil in 2010.
No criticism aimed at the OP or anyone else here, but this is an example of being gullible to media slanted pot-stirring and ignorance by many Americans of our (onerous) system of taxation. Of the $9 billion annual revenue which funds the NFL (league offices, teams, players salaries combined) I would be surprised if half or more is already confiscated by the taxman - Federal, State, local. Tax the league offices as well? Guess what: the taxes on the league offices would, in turn, be passed on to the teams who would, in turn, raise ticket prices again.
Also: fact-twisting by the media about Exxon's taxes. The owners of Exxon (likely you and me, your parents, grandparents and/or friends own its stock directly or via investment portfolios) are subject to double taxation: Exxon's corporate taxes, and your personal income taxes on Exxon dividends.
The author of the petition should be sent back to junior high school social studies classes.
2. Their "investment" revenue is mostly interest. 501(c)(6) organizations can absolutely place their money in investments. They just need to be primarily supported by membership dues and other revenue related to its exempt purpose (which the NFL obviously is).
3. Player fines are donated to charity. Coach/club fines are reported as revenue.