Trippin, part of the rationale for doing "daylight savings time" is that if people are active during daylight hours, then you save resources that would otherwise be spent on lighting office buildings, etc. So instead of just adjusting the hours when we do things, working 8 AM to 4 PM instead of 9 AM to 5 PM, we just adjust the clocks.

Of course, instead the cost of darkness becomes a personal expenditure since we light our homes instead, but that's a much smaller expenditure than large facilities. Until last year, the time change period was actually shorter, but there was a federal bill in the US to extend daylight savings time with the notion that it would help save lots of money by reducing the amount of electricity use.