Hit Dice and spell slots are character resources. They are not player resources.
In what game world does the *character* wake up and say, "Hey, I'm going to spend a hit die now?" The tomes in the library of the Great Sage Snarglepants do not contain the phrase "hit die". The Hit Die does not exist within the game world. Arrows and iron rations might be character resources, but things that do not exist within the fictional world cannot be character resources.
And, in any event, all character resources are player resources anyway, as the character is itself a player resource, and so character resources are the player's by inheritance.
D&D is not a game where players invoke narrative control beyond the capacity of their characters to cause real change within the world.
Again, with the "this is not D&D" thing. I am sorry, but your personal definition of what constitutes D&D carries no weight. You are not an authority that gets to dictate the One True Way of D&D. To *you*, maybe these things are important parts of the experience, but you don't get to say what's important to others. You are going to have to come up with something a lot more powerful than, "I say so," before you will be in the least bit convincing. And, before you go there, the traditionalist, "it has always been thus" will make you look like a stiff follower of dogma. History is informative, but not proscriptive of the future. What Gygax did does not prohibit me from doing something different.
Give me a real reason why this is so danged horrible it cannot be considered a part of the game, and then we can talk. Otherwise, as I said - if you don't like it, don't use it. But stop trying to rain on other people's parades, please.
Me, I'm not a fan of anchovies, so I don't order them on my pizza. But you don't see me trying to tell people that if it has anchovies, it isn't pizza.