Affiliate Marketing and MLM - Vive Le Difference

I have to start this particular article with this disclaimer. I have nothing against MLM (Multi-Level Marketing) or those who have found their niche within it, unless they don't know what the word 'NO' means or they don't realize that a funeral is not the right place to sell toiletries or washing powder (why did those two come to mind?)
I've have been seeing Affiliate Marketing compared to MLM for years now and to be quite honest, I really thought that the difference between the two was so obvious that a comparison could never be made. Not so! People, who obviously don't understand what Affiliates do and how their programs work, are assuming that it is just another 'MLM' business model. Nothing could be further from the truth.
So, my mission today is to demonstrate the (obvious) difference to those who would compare the two, once and for all.
Firstly, the popular MLM business models that have been around for years, long before the advent of the Internet, are well known to most people, at least, I assume they are to those that make the comparison I speak of. Otherwise, on what do they base the assertion that they are the same or even similar? The two most well known MLM businesses, we