I have been doing the above for years. And in the summer, I do a lot of those errands on my bike, especially getting fresh produce from the local farms.
I have a 2003 car that has 64,000 miles on it. At this rate, it is going to last forever. Granted, we use DH's car for trips, but still. My friends don't think twice about driving all over the place.
My friends in my grad program make fun of me because I don't drive into the city. I drive to the terminus of the train, park in the garage, and go 2 stops, where the university is half a block away. The university reimburses me for my parking fees.
My goal now is to find a job when I graduate where I can commute, or at the least maintain the type of riding/driving I do now, while doing my internship. Where I am at now is probably at the edge of commutability for me (16 miles). The main issue is the last mile is through a very sketchy part of the city and on the way back there's a traffic situation, involving a one way thing (round a bout, sort of, with a large dash of horrible drivers who don't obey the law).
I do what I can, and am OK with the knowledge that I drive a whole lot less than most of the people I know. But, I do miss commuting.