I read in a medical paper that barefoot walking is very healthy for the feet.
You can say it's healthy but not in the sense this pill is good for this condition but in the sense that it's the natural way people are genetically made to walk and run. But because your feet have adapted to shoes (not in the good way) it will be hard at first to go for long distances: start slow with small walks in the local park on grass or sand and than move up to soil, hard soil and than cement and other surfaces. But you find more information about this process on this site:
Even though it has horrible graphics in my oppinion it's the best resource for barefoot walking/running.
p.s. I also did walking, running and climbing barefoot in the city but not for long distances. I don't think there would be any chances to get injured if you simply walk (I only got injured while sprinting) but if you walk for long distances anything can happen so it's probably advisable to get an antitetanos shot or simply wear shoes in the areas where you don't want to pay attention to what's on the ground in front of you - but by all means take of your stink bombs to chill out in a park, gardens, etc.