You have to worry about both of those things. Why? Because instead of forcing the placement of every steel beam and the sale of every chicken sandwich to pass through the hands of an intermediary who both profits from and regulates the action, we just decided to regularly inspect places where problems were likely to occur, and to investigate reports of possible violations.

The argument you're making would work just as well for recording all human speech at all times, and processing it for suspicious topics - which is totally currently technologically possible. Even if it weren't, why not require that all conversations be had over a telephone? That's pretty much the same as having rules about the amount of arsenic allowed in salt...