Rolling to hit vs. Memory Lane

I was just thinking about the time I gave D&D4 (Eberron) a not-so-charitable shot. The GM was very big on her Overarching Plot, see, and wanted to just kind of bring us up to speed during the first session.
I was unaware of this/didn't care to cooperate.
In my introductory scene as a priest of the hearth-goddess, I nearly got into a screaming match with some lord over the ethics of my assigned quest. This was not because the GM was playing him in any particular manner; I was trying to get an angle going for what my character was like, and "religious fanatic" seemed a good one.
Wouldn't you know, the GM was downright puzzled at my overacting. I had assumed that if I was placed in a scene, I was free to do as I pleased in it, provided I didn't just wander away (which would, legitimately, be kind of unfair). But it felt like I was supposed to just keep hitting the "A" button, as it were, to scroll through the NPC's dialogue.
Not down for that.
Second occasion of my ridiculousness: the War-forged member of the party gets some guff from a city guard. I ask him his superior's name, and he gives it, but the guide leading us around the city informs me immediately that "That's just how things are in this town."
I shoot back, "I am a man of the gods! I cannot stand by and allow such petty outrages!" (or some such high-flown diction)
He shakes his head at my naivete. I, the player, grind my teeth a little at being stone-walled... again.
Anyway, I ended up going a little crazy later on in the session while some of the other players (5 of us, altogether, I think) have a very extended conversation about... stuff.

I told the GM afterwards that this wasn't the game for me. Her response was a polite version of "no kidding." I had wanted to give it a try, and I accept that D&D4 can be a very different experience than this (whether it's to or not to my liking is unknown, yet).
But, looking at various story-games threads about Apocalypse World, about sandbox games, basically about very character-centered, player-choice-matters games, makes me wonder what I could have been thinking to try something a bit more 1990 (i.e. the middle wave of AD&D, where GMs stopped practicing Old School Zen and started all that stuff that Ron gets anger-y about), knowing my own proclivities for Maximum Protagonism!

Anyway. Let this be a lesson: never play in a game just to be polite if you suspect you'll really hate it. Even if you might be pleasantly surprised, being pleasantly disappointed is just too much of a waste of not just your time, but the group's.

/out