At this point of tike there is 14 stuff packs, each cost 10$ that would 140$ for stuff packs compilation and you would hardly get enough content to expand on the base game and keep you interested for ...
This is a game, not necessity. It's also not required to purchase packs at full cost, as many are offered at a discount, including at time of launch. By the logic the OP is using, EPs and GPs are expensive. Let's agree to disagree. We all have different values, preferences, income. Buy what you like and can afford. And everyone is happy