this is dangerously close to being a rant. we discourage such things.
while i would never ever try to convince you to shop anywhere you didn't want to, i'm unclear as to the exact purpose of this post.
i highly recommend you look up their management address and write a letter explaining all the facts behind your unhappiness. i hope you'll give them a fair chance to make it right. if, however, you are firm in your choice to not shop there again, there isn't much point in saying so here. you need to tell them.
HOP is a huge, internationally famous and respected shop. it stands to reason that the overwhelming majority of their customers get good service.
your case is unfortunate but warning others away is unfair and without foundation.