fujii,
Just don't travel to the US, UK or anywhere else (including AU) where this ICAO compliant practice for aircraft cleared for a visual approach is ever used.
What you really mean is you think it is dangerous, as a reflex reaction, without any sort of risk analysis, because you don't understand what is happening, and you don't actually understand the various rights and responsibilities of controllers and pilots in command.
Just a clue: It is always the responsibility of the pilot in command to be satisfied that the runway us clear before landing (or takeoff) ---- regardless of the clearance.
If you want to have a look at how various people can tie themselves in knots on such a matter, particularly when serious vested interests are concerned, get all three complete inquiries into the day the TAA B727 on takeoff hit the Trans Canada DC-8 that had just landed.
Tootle pip!!
PS: You should probably also avoid the parts of the world where all the often quite busy airways systems are G or E airspace, and I do NOT mean USA below 10,000'