No, pebbles in the shoe would just draw attention to you by people looking for someone with an unusual gait. While I don't know if that detail about the U.S.S.

No, pebbles in the shoe would just draw attention to you by people looking for someone with an unusual gait. While I don't know if that detail about the U.S.S.S. is true (it probably is), there are "tells" if someone is consciously or subconsciously thinking about a firearm on their body.