Most Mexican restaurants I've been in start you off with free chips and salsa (which are not nachos).
Most sit down restaurants I've been in that bring you bread to start off do not charge you for it, even when you ask for more, which I often do, especially when the service is slow, because I love good bread and butter.
But this convo does remind me of the first time I was in Paris, near the beginning of my 5 years abroad. My friend and I arrived in the Gare du Nord train station in the morning, famished.
We sat down at a cafe in the train station. There were croissants already on the table. As per American custom, we assumed they were free, and scarfed the entire bowl down. We did also order main stuff, btw, but were shocked when the bill came and we were charged per croissant as well. It was a minor cultural learning experience. <shrug>