I'm in Oregon, and that's the case - about $30 extra. More people than you think don't have access to supplemental documentation required to meet extra requirements – people who don't have current travel documents, people who've just moved into town, people who don't have current documentation of address (e.g. the homeless, people in the foster care system, etc.)

It's pragmatic to have: plenty of people don't or can't fly, and the cost of supporting this option is marginal.