A morning bus for commuters, a late morning bus for shoppers, a mid-afternoon bus for shoppers and school/college students and a teatime bus for commuters.
Perfectly useful for most day to day occasions.
Indeed. Here, one route is 3 buses a day, another 4 a day timed exactly that way, and both do shoppers, commuters and college students and are well patronised. It's when a route is one or two a day that it tends to be a single purpose, shopping only type service in my experience.
Although we do have a once a day route to serve both a local government and a central government site.