You would be correct. US BLS survey data consistently indicates that a majority of Americans cook at home and almost never eat out.

Affluent urban professionals, of which there are many on HN, may have their perception of the world influenced by living in a bubble of people that eat out several times a week. Until I saw the BLS data, I assumed more people eat out than actually do because almost everyone I know falls into this category. But having been poor once, I definitively know you can eat cheaply and well by cooking at home.