Trike encounter or not, I always liked walking through that area, since it adds to the JP island feel with all of the computers and field stations and stuff.
They could easily turn it into a photo-op place with random dinosaurs, like they did with a few of the other dinos.
As for putting the trikes into the JPRA, I'm guessing two things. First, I'm guessing they're probably MUCH more expensive to operate than the normal ones, and second, I bet they're not weather resistant in the same way the ones on JPRA are. I could be wrong, but thats my guess.