My kid loses 3 coats a year (dyspraxic, so something we live with - if he's thrown off routine, stuff gets lost), so the idea of spending that much on a coat is already crazy.
Hell, I doubt I'd spend that much on a coat for me (I think I've gone up to 300.. for a woollen dress coat that will last for many years).
I'm normally against all this coat regulation I see (black coats for schoool kids for instance is mad. Have them wear bright, reflective stuff), but I can see why a) they wouldn't want to risk accepting liability for this stuff, and b) why they'd want to enforce some kind of standards around cost of coats.
So I find myself caught between common sense and principles.
On the whole, I think that I agree with so many others here - if you can afford to spend that on a coat, you can afford a cheap one for school.