There's several reasons for me personally.
Visually, it's very different from the two piggies we have in the game now. Even though it occupies the same biome and continent as the warthog, visual difference also plays a part in what's wanted.
It's very common in zoos. It's also in my local zoo, which isn't a reason for everyone wanting it of course, but it is for me.
We have low representation of the suidaes. One from the base game and one from DLC. I understand why people would want a peccary instead; even though it's in a slightly different group of animals, it's still overall very similar in looks, behavior and design.I just would personally rather have the RRH. (an aside, I also make the case for another equid as we've also gotten only 1 in base game and 1 in DLC, but that's another thread lol)