You inadvertently made a lot of arguments for the other side. You admit that gaming is hurtling towards, if not currently mired in a wasteland where the entire game is sold piecemeal. You admit that people paying for this bullshit is why it continues. We're already to the point that we're not talking about extra pizza toppings anymore, we're actually redefining the concept of "Pizza" as a whole.
Even as a late 20s male, I've watched how the equilibrium has balanced for years - There was a time when your game came with engine/mod tools for the $30-50 entry fee, and ALL the content on the disc or available at day one was available for you for the entire price. You even expected not only bug fixes but some actual FREE content in each patch, as a "Thank You for buying our game. Please think of us when our next project comes out". Bigger blocks of content were sold as complete expansion packs, for $20-40 and often DOUBLED the content of the original game. Look at the Doom 2 Expansions and Jedi Knight's Mysteries of the Sith - it was basically a whole other game as long as the original campaign, with completely new art assets, powers, etc.. Now...compared Mysteries of the Sith.. to Modern Warfare 2's Map Pack. Seriously. Is that Modern Warfare 2 Map Pack literally HALF the amount of content as Mysteries of the Sith? THAT is what we're upset about today. (Don't mention inflation or whatnot, it isn't even a third of a quarter of MotS)
The very concept of "pizza" has changed. It used to be that you may have paid for extra toppings, but today your same $10 pizza comes with no cheese, no tomatoes, no spices, and only 1/4 the bread which is spongy and low quality. Even when you do get lucky enough to find a parlor with a fairly complete basic definition of pizza, their toppings aren't $5 to outfit your pizza with high-quality pepperoni, but rather $5 per pepperoni slice! Would anyone put up with this? Sure, you could be told "Oh, well just get one green pepper and one pepperoni then if you don't want to pay, it doesn't affect the rest of the pizza", but you're be eating a bland pizza remembering the time when you paid a fair price for flavor. If every parlor does this and everyone keeps buying pizza, thinking its normal eventually you're paying $15 for stale, tasteless bread which is being championed as "pizza".
This is the problem. It only takes a very small return on investment for this kind of bullshit to be profitable. So when other people pay $5 for a hat or horse armor, it means that I have to live with incomplete, castrated game content in the future because it would take 90% of us boycotting the game entirely to make our point, and only 5-10% of buyers buying a piece of DLC to put the miniscule amount of work into it to create a profit. When all other regulations and ethics of business are stripped away, the last line of defense is the consumer. The consumer has shown they will well..consume...anything, nomatter what kind of turd sandwich it is, so business has lost any desire to try to cater to the customer, as the AAA gaming industry has figured out that a certain (smaller?) percentage of vacuous wallet-open drool monkeys is the most important part of their financial success. Why go after old codgers like me who have standards and remember quality, when there is an up and coming crop of kids who buy whatever they're told without any question?