Do these readable Visas and passports say where you will be staying?
A record in a database is far more valuable than a dump truck full of little pieces of paper. Who is going to decipher those? If the visitor knows where she will be staying, that can be typed into the computer by the agent. However how many visitors can be sure where they are going to stay each and every night of their trip? What if they show up at the hotel but their room is flooded and there is no replacement room? There is no penalty for not living up to what one wrote on that piece of paper; and there is no technical capability to follow up; and there is not even a desire to do that. Those Chechen brothers were here legally, and the police knew where they lived - so what? I don't think pushing for a more efficient and omniscient police state is the way to go.
This form only helps locate visitors who want to be located. Those are not a problem. A troublemaker, on the other hand, can always say that he plans to stay in a certain motel that he found on the Internet. Of course he won't be there. How would you know? What do you do after that? If you catch up with him, is his action a crime? There is no law that forces all foreigners to register their location with the police and keep it updated. (But parolees are required to do that, as I understand.)
Fact of the matter is that once someone is admitted into the country, that person becomes, for all practical reasons, invisible. The only chance to find him is when he gets stopped by the police and tells his true name instead of some generic Jose-Maria Gonzalez of some random year of birth and of some random address. Local illegals have many aliases like that, and the police dispatcher just replies with "not known." Lacking a warrant, the LEO cites the guy for something and lets him go.
No.