As an Australian I can comment on this, theres this wonderful thing called "Context"
At McDonalds they refer to them as fries, but if you ask for a large chips, they know what you mean. If you go into a petrol station and ask where the crisps are, nobodies head explodes. If you go into a place that has ALL 3 (french fries, chips and crisps) and say "Can I get some chips" the person will ask for clarificaton.
British roots and American television has made OUR english quite flexible.
Usually not a problem because of context but you can easily specify hot chips or packet chips in places where they might have both such as a school or sports canteen.
It's communicated by context cues the same way one word has different meanings and context points to towards the meaning the person is communicating with a word
Though it does get annoying when the context cues are missing for example someone asking you if you want chips and not specifying what type
I'm guessing Australian language for "chips" calls them both that because they are a product made from potato that is usually salted and the two in the image are just different styles of the same potato product