What makes you think users were happy? If people liked that content so damn much, why was artificial vote manipulation needed to make it visible?
Subreddits and Reddit are in a symbiotic relationship. Most subreddits depend on the mainpage to deliver them eyeballs. Some subreddits depend on those eyeballs they receive from the mainpage to create good content and PR for Reddit.
Let's be honest, there's wealth of content on Reddit, enough so that users might not miss some content going missing randomly.
<Personal opinion starts here>
However, I personally believe that Reddit should cultivate stronger content than cat memes and animated images. Getting Stephen Hawking to answer questions from the public is, in my opinion (from a site culture and company PR perspective), more valuable than the 1000000th Star Wars prequel meme to appear on the front page.
Though I think a better comparison might be the eating habits one other people have made. Veggies might be better for you, but most people will choose to eat junk food. I just think that's sufficiently solved by natural selection.