the rules should take a backseat to whatever is happening at the game table. Rules are guidelines, not laws. And they should never dictate the game/story flowThis is the classic mantra. Most recently run into here.
If you think of the rules as being like a steering wheel (and brake/accelerator), it's hard to make sense of these - you have to put them to the backseat? Where you can't reach them?
It's the strange starting part - why have them to begin with? Is it a need to simply identify with a certain game - gotta have the book, or you aren't a real player of RPG X (whether X==D&D or some other RPG)?
It's like an urgency to both draw them close, but then also push them away.
I suspect it basically comes from gamers who have never, ever encountered rules that do what they actually want to do. They just keep encountering encumbrance rules, or weapon vs armour charts, or even to hit rolls and...it's like way, way, way over there in group B. And what they want to do is in group A.
And they've never encountered a rule that helps or adds interesting things to group A.
So they assume rules really have nothing to do with what they like. Or parochially, rules have nothing to do with roleplay.
Side note: Somehow I spelt parochially right the first time, but not encumbrance! Bad gamer!