Attending an NFL game is going to cost you a fortune
Well, if your team is any good it is going to. In many cases, even if the team has zero chance of selling out the game they will still opt to charge high prices and just have half an audience. I suppose it is easy to understand why. There are a ton of staff involved in the operation of an NFL home game and even if the earnings are good, there is a formula in place to determine if it is worth their while to open. I don't know what that formula is, but this is why even terrible teams routinely have ticket prices that are $100 or more.
I recently ran into an article about how ridiculous the prices are for Kansas City Chiefs games. The article in question said that the cheapest tickets for a family of four to attend a home game would cost $725. By the time they got a hot dog, paid for parking, maybe some candy for the kids, the cost goes up to nearly $850. I find it kind of terrible that they would charge for parking even though you already paid an outrageous price for nosebleed section tickets.

src
I don't know if you have ever been to Kansas City or not. I have because I have relatives in Missouri and I can say with first-hand knowledge that there really isn't much to get excited about if you live there. Other than BBQ and sports teams, people just basically drink and try not to think about the impending doom that is winter. Perhaps this is why the Kansas City teams tend to sell really well and right now are the most expensive team in the NFL to go see a home game with.
If you live in a city that isn't KC, don't get too excited just yet because the league average for 4 tickets is around $550. Once you include parking fees at most stadiums it will cost around $150 minimum for one person to attend a game alone.

src
I suppose we could get upset about this or just accept something that I have been saying for quite some time. Sports clubs are not about the sport in question for the most part, they are about making money and man oh man do they do a lot of that. The Chiefs value is $3.7 BILLION and those gigantic stadiums don't get made for nothing.
One valid complaint made by people that live in the county where Arrowhead Stadium is located is that they paid taxes that went to the Chiefs for building purposes and now some residents are demanding discounted ticket prices for said people. I would be willing to bet that this request simply goes ignored unless they make a much bigger stink about it because the legislators that approved the tax money to be given to the Chiefs are interested in the overall economic benefit for the region during the home games, as well as the tax revenue that comes along with it. I doubt they really care if the average Joe can afford to go to a game.
Sad but true: Sports are about money, not about the fans or even the sport.