Why do the Americans almost never eat soup nor drink an "ap�ritif"?

II used to live in the USA and I wondered why, in most US families, soup is not an usual part of the daily meal and also why most people never drink an aperitif before dinner. In Belgium, we eat soup very often and it is usual to drink an ap�ritif before to start the meal. When I watch old TV shows, like "Bewitched", it looks like it used to be like this until the sixties. So, why not anymore?