Assuming that nothing in how the body works happens for no good reason:
The fact that we enjoy it means that our body rewards us for eating it, something that most likely means that it's something the body wants us to do. If it was abundant, though, that'd make us eat too much of it (which is what's happening today) unless there was something to stop us. With salt it's possible to eat too much: that makes us feel bad. That suggests that salt was abundant, otherwise we wouldn't need the counter system. The lack of a counter system for sweets suggests that it wasn't abundant, at least not to the degree that we could eat enough of it to prevent us from reproducing.
Our bodies run on sugar; sources of sugar, such as fruits and starches were not hard to find.
Eveything we digest is converted to sugar, be it fruits, bread or meat.
Regarding the link:
That some of our ancestors two million years ago might have, or might not have, eaten mostly fruits doesn't say much of anything about how Homo Sapiens work. In the article they say that even the Homo Erectus were omnivores, and that was 1.5M years ago. Things have happened since then...