This week I've started reading The Design of Everyday Things after HN recommendations, and the author makes a distinction between objects themselves, and their 'conceptual models', which may differ for the designer and the user. A single user may even have multiple, conflicting conceptual models of a device and its use. These are sourced from what he calls the 'system image', or overall set of information available about the device including past experience, appearance, sales literature, manuals, websites, advertising, etc. Needless to say, people can operate successfully on an incorrect mental model as long as it serves its purpose.

PS. Australian here. Yes, people do speak like that, but I agree with your conclusion.