There are people who have flexible work schedules but most don't. We are still largely tied to 8 to 5 (which becomes 6 most days). Yes, we can leave the clocks alone and change the start of school for the 9am sunrise months (if year round DST) but that disrupts daycares, high schoolers with after school jobs, and the businesses that employ them. Doing the time shift twice a year keeps schedules the same. No one is going to playh mini-golf at 5am, so . eliminating DST takes money away from outdoor attractions.
So how about businesses, schools, etc. moving their start times by 1/2-hour ... right in between ST & DST? When it comes to time zones we're pretty much stuck with 1-hour increments but not so with other schedules.