I once read an interesting article on this by PTC, his summation was a boot will direct your foot and leg where it wants on placement, a shoe will allow your foot to make its own placement.
Don't forget there are now big debates in the USA regarding walking and running barefoot as our anscestors did, and wearing the 5 toed Nike slip-ons.
Wouldn't fancy it myself, i wear both depending on route, weather, and underfoot conditions expected.