What if a law only has consequences for the people it's intended for?

Let's say you have a requirement that all TVs should be registered, so you can make sure every TV owner has a TV licence. You find an unregistered TV, but the owner has a TV licence. Does it make sense to confiscate the TV? What purpose would that serve?

Let's say you have a law that all people entering a country must be scrutinized to ensure no serial killers get in. You find a guy who hasn't been scrutinized, but he's not a serial killer. Does it make sense to confiscate the guy? What purpose would that serve?

>Let's say you have a law that all people entering a country must be scrutinized to ensure no serial killers get in. You find a guy who hasn't been scrutinized, but he's not a serial killer. Does it make sense to confiscate the guy? What purpose would that serve?

To ensure that people go through the checkpoint in the first place? For instance, the point of airport security checkpoints is to make sure that no terrorists get on planes, but if there's no penalty for you jumping the fence, why would people even bother going through the checkpoint?

And all of this is ignoring the other purposes of immigration policy, eg. preserving jobs or whatever.