Actually a bar of soap in a sock can do some serious damage, I kid you not.
Oh, I quite agree. However if there is any dispute about the use of a sock with sand in it, if you lose the sand, it is not against the law to carry around a spare pair of dirty socks.
It goes to the theory that most anything can be made into a weapon, usually with just minor modification to optimize it.
Police are trained to operate like animal predators, both in looking out for obvious unusual behavior and things that do not go together, like a bar of soap in a sock. But if you act casual, claim aggression on your part was just accidental, and have a pair of dirty, sandy socks, the cop will often accept what you say at face value.
I knew one martial artist who had perfected the art of “accidental” attack, profusely apologizing throughout while beating the snot out of his opponent. Everything he did *could* have been interpreted as “just clumsiness”.