Walk is a mobile four letter word.
I was entering a local store today, and a neighbor commented that they didn't see my car. "Oh, I walked." They seemed a bit surprised - the store wasn't in a very walkable part of town.
I like to walk when I can. I work from home, and my job doesn't give me a great deal of opportunity to move around as part of my job itself. We're encouraged to exercise, but I don't like to exercise for exercises sake - it is more difficult for me to motivate myself to "work out"... but I do try to make sure that I get out and move whenever I have the opportunity.
Walking makes me feel like there is a purpose to what I'm doing. I'm not just exercising because "I should", but I'm getting a bit of exercise, and accomplishing a task or errand at the same time. The errand is the objective - the walking is just the method to do so.
Yes, it takes a little time. And it isn't always the best conditions to go for a walk. And I'm sure that I should get in more exercise than I do. But going for a walk seems better than the alternative - not doing so.
So try it. Walk where you can instead of going for the most convenient solution. You may very well take it in stride.