You kind of answered your own question. Games cost $60 or they're free, and then make additional revenue through cash shop selling cosmetics/boosts. WoW charges a full game price for each expansion, $15 a month subscription, AND adds store on top of that. The difference is obvious. We're paying a premium price for a product yet we receive scheme upon scheme of store baits.
The argument of not using the store if one doesn't like it is invalid because WoW's entire monetization system is convoluted and perverted version of itself. Games like Dota 2 finance their e-sports from the store, and that's completely fine because base game is free and there's no subscription fee. Elder Scrolls Online is another good example with their buy to play plus store. WoW players who already pay too much should get these items through interesting in game events and quests and not be forced to pay a third time.