I don't think the comparison with food and other products makes a lot of sense. All the ingredients of Oreo's get more expensive because of inflation, and as a result Oreo's need to get more expensive as well. Absolutely, development costs have increased for AAA titles, but getting the game from the developer to the consumer has never been this cheap.
Digital distribution and Blu-rays are extremely cheap. Compare that to cartridges that used to cost anywhere from $15-$30 each. If developers would increase the price of games they would (1) lose a lot of money, because people would buy less games, and shipping a few additional copies is very cheap anyway, and (2) consumers would have to pay more to get the same game. Everyone loses.
I can't exactly make the jump from 'if games were more expensive there would be less DLC' either. DLC didn't exist in the past because game systems didn't support such functionality. That's it. Companies will keep on making DLC because it's easy money for them, increasing the price of games will not change that.