Luis, because in english, to put something doesnt have to be directional. When saying "put on" or "put inside" you are talking about the fact that its now there and you did it. You are not necessarily talking about the movement towards. You can also say, "put into" or "put onto" this is directional. In the langauge i am learning i must say it the way you say. Because we do not need to in english, i often make mistakes.

At first remove the giraffe from there and then put an elephant instead. 

Luis it's not that you were completely wrong, it's just that the original statement that you corrected was not actually wrong either!

Hello Mewe, Thank you for your comment, but I don't know why I was not right here.

As I know, "into" is the preposition of movement and "inside" is the preposition of the location.

So I think when you want to put a giraffe into a refrigerator, It means that you want to move the animal into the refrigerator. "Put" indicate a movement, That's why I think "inside" wasn't correct here.

Of course you are a native speaker, so I think I am actually wrong, but I don't know why.

Would you please explain to me, I would greatly appreciate it! Thank you!

"put inside" is correct even if bro Luis tells you its not.