In the GTA alone last year, there was major flooding and an ice storm. Many homes were damaged. Some of those, almost certainly, were in the process of being sold. What happens if you are about to buy a house, you think it might have been damaged, and the seller won’t let you back in?
There is an old case called Harkness v. Cooney that specifically deals with inspecting properties before closing. If the seller refuses to allow entry, then you could rely on this case to require an inspection before closing. An easier route, however, is to save an extra visit for shortly before closing. Even if there have been no natural disasters, you may want to be sure that no holes were punched into the walls while the sellers were walking out the door.