How to make me not buy a book from you

Visitors to this site may be under the impression that I buy books on a regular basis.  Many books.  Quite a few books.  Rumors that I will buy books under any circumstances are not, however, true--outward appearances to the contrary.  If you are a seller and would like (for reasons unclear to me) to dissuade me from purchasing your books, one of the best ways to do it is to rack up your shipping prices beyond any resemblance to the actual cost.  I have no objection to someone making a profit on shipping, but charging 25 pounds sterling to mail one not-very-large novel from the UK to the USA is...excessive.  I know this, you know this, your post office knows this.