IMHO the best way to view emails like your one to Emirates are that they are a way to get it off your chest by having a rant. It feels so much better afterwards and then one can get on with life. Expecting a meaningful answer does not help, it only prolongs the angst and hoping to get some kind of compensation is futile in most cases. Take comfort from the fact that you know that the response is most likely to be a canned one along the lines of "we are sorry that we did not live up to your expectations on your recent flight with us and we look forward to seeing you aboard another flight soon" - then when such a reply duly arrives in your inbox you can be happy knowing that you were right. This mental approach works wonders for me!