the capitals at the end were accidental, I used caps for GSP and forgot to remove the caps lock

if a buyer refuses to pay the customs charges they lose the right to  a refund,

so sellers do not have to get involved in paying customs charges

if a seller doesn't put the correct code on a GSP package it can cause problems at the GSP centre

  only UK citizens are charged UK customs fees when they import items into the UK, so what have law suits in America against American carriers got to do with UK customs charges?

customs charges are set according to the declared value and item description given by the seller on the customs declaration form, so, if the SELLER fills this in incorrectly the buyer will be charged incorrectly.

you still haven't given an example of what has happened to you and what you are actually complaining about!