if you spend 3 hours a day in a car

That's a lot more than most people do. Conservatively assuming that all travel is via car, the 2014 average on the American Time Use Survey [1] is 1.11hr/day [2]. At $1 = 1hr, that's $1.11/day.

But I do agree habituation is significant here. People probably felt similarly about seatbelts but I don't notice mine.

[1] http://www.bls.gov/tus/tables/a1_2014.pdf

[2] Broken down as, in hours per day: 0.02 for personal care, 0.10 for eating and drinking, 0.04 for household activities, 0.27 for purchasing goods and services, 0.08 for caring for and helping household members, 0.05 for non-household members, 0.27 for work, 0.03 for education, 0.04 for organizational, religious, and civic activities, 0.21 for leisure and sports.