NIKON warranty a *******

I purchased a relatively expensive set of Nikon binoculars and the eye piece was damaged while under warranty. I had to drive all the way to Midrand to hand in the product and was advised that they would submit it and advise me when it was ready for collection. I was informed by email that they don't cover eye pieces in the warranty and that the cost will be over R 1300.00 to fix. I now have to drive all the way back to Midrand to collect them and sit with a broken eye piece as I really don't intent spending that kind of money on something that should be covered by warranty. Why could the service assistant not have told me this when I was there and why is this not covered under warranty? An item that costs 20% of the purchase price to repair should be under warranty or such exclusions should be clearly stated on the warranty exclusion.