Dogs and cats in particular are an important part of your Sims household. They may not be able to get fully-fledged jobs like before, but they can be trained to hunt, and are fully controllable this time around. So, while your bread-winning Sim is away at work, you can stalk other people’s low-maintenance animals with your cat (if you want to indulge your evil streak), or locate valuable items with your hound. These are the game-changing benefits of owning pets, but they can just be mere novelties if you prefer the hands-off approach.
Horses are a great addition to the fold. You can train them up and enter them in competitions and races to earn a tidy amount of Simoleons (the in-game currency for those unfamiliar). Similarly, your Sims can acquire horse riding skills and make a lucrative career out of it. Horses can be adopted for free at any time, though you can always take a gamble and attempt to train up a wild one. These may come with pre-loaded traits and skills, yet will be less receptive to your efforts to teach them new tricks.
I just pooped.