Plenty of people live all over the eastern half of the US. It's only the western half that is mostly empty except for the coast.

Here's the population by time zone, in millions:

    Eastern:  150.2 (47.1%)
    Central:   92.3 (29.0%)
    Mountain:  21.3 (6.7%)
    Pacific:   53.0 (16.6%)

https://www.quora.com/What-percentage-of-the-US-population-l...