£40 postage in the context of an £11K purchase is cheap. It isn't the postage that's stupid, rather the item for sale.
If I ship an item valued at over £250 abroad, the PO no longer insure it. It has to go by Parcelforce as a parcel, and the cost of that is about £50 minimum, with some rates as much as £150 or so if the value is higher. People tend to automatically dismiss postage as a trivial amount, but the last few years have seen significant changes in the system. And if on eBay you also have to add on their fee and that of Paypal. Anything under £3ish and you are short changing yourself.