American food is derived from English food, and English food was very heavily influenced by the Normans, who were French. France and England are also very close geographically, and share a lot of cultural things, such as food. Not to mention there were so many early French settlers of the Americas that you probably eat a lot of French-derived foods without realising it.
Some stereotypical French foods include things that no-one probably eats, like escargot (snails) and grenouilles (frogs-legs), as well as a lot of things that are commonly eaten, like paté, croissants, cheese, sausages, wine, quiche, and so forth, as well as more bread and sweet little pastry and fried and baked things than you can poke a stick at.
I haven't been to France since I was quite young, but my sister was there a month or so ago and reports eating things like lasagne, quiche, soup, and vegetable bake for dinner, and toast and jam for breakfast. She hasn't said what she had for lunch because she's still a little stunned with her first experience of school-provided lunches to comment.