My commute is 10 miles each way, 4–5 days a week (I often work from home 1 day a week), currently all by car. So that's 80–100 miles a week just for commuting, and then probably another handful a miles a week for basic errands (groceries, etc.), then maybe some other longer car trip outing on some weekends. I'm probably just over the 100 mile mark on average.
I should probably make an effort and give bus transit a chance. Tough to allow for what will probably be double or triple the total commute time, though.