When I lived in London there was obviously a difference between the two, but neither were objectionable. Lots of people would walk to places rather than wait for public transport, as a way to get steps up and just because it's more certain time wise and less likelihood of being squashed into other people's armpits. But I live in Dublin now and often have people seeming shocked that I would walk somewhere because I need to go to that place when those same people 'go for a walk' because it's healthy. But, to me, unless I have a time crunch that will require me to drive somewhere else afterwards, there's no benefit in parking as close as possible and all walking is equally valuable even when there is a purpose beyond just walking for walking's sake.
For instance I have a doctor's appointment soon and the hospital car park is massively expensive and awkward with tiny spaces, but I can get on street parking for a fraction of the cost that is at most 12 minutes walk away. Last time I used the hospital car park I spent almost that long queueing to get into the car park. Quite a few of my friends have been to the same hospital and also hate the car park but would never consider parking elsewhere and walking and kept giving me reasons why I shouldn't do it either. Or when I met my Mum and DB for lunch in a place that happened to be a 20 min walk from my house my Mum was very insistent that I should let my DB drop me home afterwards, even though she knows that I walk a brisk hour along the very same roads for exercise several times a week.