I have "crate trained" puppies for the past five puppies we have reared, and our experience is that (1) when very small, crates are used as the puppy's personal space - gives them a safe retreat from family hurly burly, where they can safely observe the goings on in a household without being in danger of being trodden on etc etc (2) if, we have had to leave a puppy for a couple of hours or so, not only is it safe, but so is the house!!
Before crate training, I have lost count of the cost of damage inflicted on our house/possessions (most of which, as you rightly point out Gonzo, should be put safely away;) ) by our previous 7 or 8 dogs as puppies

! You cannot put doors, walls, tables, chairs and settees away safely!!!
What I was saying was, that Freya has not had the door shut on her crate for nearly 3 months - she COULD have created havoc in any of those 3 months, but didn't - but the minute the crate wasn't there - she did!!
PS we didn't put the crate back last night - but she was a good girl & inflicted no more damage to shoes - although I did make sure that the good shoes were removed from the shoe rack - and took the decent coats and put them away!!!
Margot