I have a bufo I got about two years ago, and when I first got him he hid all the time. He eventually warmed up and felt more comfortable coming out and being seen. Even to this day, he will move his hut around and burrow all over the place. I think it's just how they act. He probably just hid because he was acclimating to his new home. Toads can be active with these things...but also, when they're comfortable, they can go into "Pac-Man Frog" mode where they just wait for food to come to them. I wouldn't worry too much--he sounds like he is doing very well!