Fishing is the only hobby. 'One of the only ways a hobbit can spend the afternoon snoozing and still get dinner' is the description. You, like in crafting, can level up, but with fishing it is much quicker, the problem is that as you get better, you catch more and more 'trophy fish' these are barter items and you cannot sell them. You can get them stuffed by a taxidermist, there is one in Bree-town. You can then decorate your house with them.