I have 2 shakes a day (first and last meal of the day), and to me it actually works out cheaper and easier than preparing whole foods, and love the taste of my shakes.
Generally have shake just after I get up and head to work (sometimes add powdered oats), then whole food Lunch at work, whole food dinner at home and shake just before bed, also have some snacks during the day such as almonds, nuts, seeds, beef Jerky etc etc differs from day to day.
So will have two shakes and two meals per day.