noglider 

Everyone's story and circumstances are different. I live in NYC most of the time, and public transit takes me just about everywhere. I ride a bike to work about two days a week, and I ride a bike to a few other places. I sold my car after moving back into the city. We also are members of Citi Bike, the big bike sharing program, and it's better for trips of two miles or less than riding one's own bike, because (1) locking the bike is much easier, and (2) we can ride one way and walk or take the subway the other way. But with longer trips, Citi Bike becomes annoying, because the bikes are 50-pound clunkers.

My wife still has her car and needs it to commute almost every day. We go upstate -- two hours each way -- most weekends, and we take her car. Sometimes she drives without me and I take a bus.

I've done some grocery runs on bike but have found that they're more convenient on foot. Stores are close by. I can't carry much on bike or foot, so trips are frequent. The kids are gone, so there isn't so much to buy anyway.

Commuting and doing errands on bike have become so common here that I frequently see people wearing bike helmets without being on bike.