That absolutely can be a thing, but I think that usually gets worked out pretty early by the difference between RAW and what I call RAU (Rules As Understood). Even gamist-centric groups have, effectively, unstated conventions they go by (which often will end up in house rules once someone notices that its not RAW, or alternatively everyone just adjusts to going back to RAW).
(As an example, Fragged Empire has a bleeding rule. In my hurry to read it at an early point in process, I read it as cutting in when an attribute went to zero from critical damage. As it turns out, it happens when the attribute goes to negative (i.e. -1 or worse). No one had apparently noticed the difference between what I was doing and/or took my word for it (often a mistake because, well, I'm sometimes sloppy) and what the rules said (possibly because it doesn't come up all the time) but as soon as someone on the FE Discord mentioned it in passing, I checked and found out I'd been doing it wrong and brought it to everyone's attention. Since the RAW rule was more benign to PCs, no one was at all upset, but its gone the other way too and people have mostly just shrugged).
However in the example at hand, this is still only a problem because the players and the GM aren't on the same page, and the GM was unwilling to cut any slack for that. Nothing about being gamist precludes understanding that mistakes and misunderstandings happen. Even back in my Hardcore Young Gamer days when it became obvious that I and the players were effectively using different rules sets regarding Fireball, I'd have said "Okay, this particular one time we'll have it work your way since you did this thinking it did, and the whole tactical setup you chose was based on it. But we need to thrash out whether we want to go by the book or do a houserule before its used again" and everyone would likely have just nodded and gone along.