You mean you walk differently on concrete than on the soft ground?
And yeah, I know what you mean with the heavy feet, normal shoes kind of force you to overstep and put the foot down in a wrong way in my experience. Some people seem to correct that straight away when they walk barefoot (like you), and some have to do some work to change it (I was/ is one of them).
Cool with inspiring, let me know how you get on with it! :)