I ate Spam when growing up in the 50's and early 60's, like others, my mom would fry it up and serve it on sandwiches or as a breakfast meat. Don't care for it now because of the salt and fat content and just don't care for the taste. My mom and sister still eat it fried and will also chop it up and make "ham salad" like stuff out of it for sandwiches.
There is undoubtedly a market for it because it is still going strong after all these years. I checked out the numerous varieties of it when shopping with my sister. There is even a package of one slice. I think it was a dollar or so. Kind of amazing I think. But then I am amazed that there is market for a package of 6 hard boiled eggs without the shell for $4.00!!