The main reason is probably, especially at mid-northern latitudes (where a huge number of people live), absent DST conventional work/school hours would mean that biasing sunlight hours on the late side--which many/most people prefer in the summer--implies it would be dark when people leave their house on a winter morning. Among other things, this means kids wait for buses or go to school in the dark.
Personally, I'd be fine with shifting a time zone or two east and eliminating DST but I understand why a lot of people wouldn't.
Personally, I'd be fine with shifting a time zone or two east and eliminating DST but I understand why a lot of people wouldn't.