Yes I know but I rairly put things in my pocket I am looking from the security pov. It is very hard to prove intent. The key is "willfully" like intent is hard to prove. In California it has been in court and the defendant won. This section was no doubt put it after these cases but can be challenged in court. From the pov of security it is very tricky. As I said all the person has to do is to drop the stuff without security noticing and they have a false arrest case.
As a security person you arrest a person that put something in their pocket and is still in the store you will loose in court, (doubt the police will even follow throught) , unless the guy is a pro and you got lucky!
A security secret: Security is about intimidation. The pro shoplifters and burglars are rarely caught and are not deterred by security or alarm systems. I have seen pro hits on houses and stores with alarms. They know just what to get and how much time they have.
Your alarm system in your home is 80% peace of mind. It will stop the kid or a homeless person from moving in but not the determined crook. Most burglaries in the US are drug addicts and they do not care.