Unfortunately it has an unintended consequence of criminals being more aggressive. If you as a potential pickpocket know they will throw hands regardless, you might as well start with maximum violence, save yourself some trouble.
Parisian pickpockets are quite unpleasant but at least you know they will not go beyond stealing your wallet while you're distracted.
Nah, the whole advantage of pickpocketing someone is you're away before the victim realises they've been robbed. If you use violence, you then have to deal with bystanders, as well as an irate victim.
I mean knocking the person out and taking their wallet before they know wtf happened, maybe kicking their head like a soccer ball if they try to get up is done in America because it works.
No. Pickpocketers usually work in massive crowds in order to rob people. If a robber uses violence in a massive crowd, they are far more likely to be detained by said crowd even if they can knock out the person they are trying to rob.
Even threatening violence in a crowd could make people think you're a terrorist, and the crowd response is going to be different than if you're an unarmed pickpocket.
That's basically how mugging happens in the USA. There are still some finesse pickpocketers, but most of them are only going to rob you by pulling a weapon out, usually a gun, and immediately threatening harm if they don't get what they want.
And in some parts of the country, a significant part of the population is armed and legally allowed to shoot back.
This just isn't true because mugging and pick pocketing are different crimes done in different circumstances. People who are willing to risk a small amount of non violent risk don't just accept a much larger risk in crowded circumstances where they are unlikely to get away with it.
Instead they are likely to commit other crimes or the same in more amenable circumstances. Criminals have bad risk assessment not none