The politics of "time" has alway fascinated me. All of China is "officially" on Beijing time. There was a single issue political part in Australia known as the DS4SEQ (Daylight Savings for South East Queensland). Their only issue was to enact Daylight Savings Time. Think of the "the Rents Too Damn High" party in NY.

Most countries not near the equator had DST at some point but now it is found mostly in Europe (known as Summer Time), US and Canada, Australia, NZ, and a couple of countries in South America. Some states like Hawaii and Arizona do not observe it. Though in Arizona, the Diné nation (Navajo) does observe it.

Historically, it was to promote energy savings because people would be active during sunlight rather than darkness. Ben Franklin thought it would save on candles, for example. Some argued that by extending sunlight in the evening, people would shop and have more leisure activities in the evening during Summer

As one who drives East in the morning and West at night, I always felt it was designed to give me more opportunities to head directly into the sun's glare in the morning.

Many here are probably too young to remember this, but we had non-connected transistor clocks that were programmed to fall back and spring ahead. The clocks got all screwed up when Congress changed the dayes for the time switch and there was no easy way to reprogram them.