They really are. If you use cheats so you can take control of your pets, their "Attention" and "Play" meter fall extremely quickly. For cats, "Pet," "Pamper on Couch" and "Feel the Love," seem to be the only actions that completely fill up the "attention" meter. All other actions like "hug" or "brush" only fill it up half way. They need to be pet about three times a day. They will eventually take care of the "play" meter on their own, but they usually wait until it's red to do so.
The odd thing is, your sim will stop in the middle of doing actions (like painting or cooking) to go pet or play with the pet, but the pet isn't always the one initiating it. Most of the time, when your sim stops in the middle of doing a task, it's your sim initiating it. I have no idea why.
My current build has a horseshoe pit and whenever my sim autonomously picks up the cat, they also autonomously choose to go play horseshoes. It's the silliest thing. They'll pick up the cat, carry it to the horseshoe pit, put the cat down, throw one or two horseshoes and then stop and sort of stand there like "how did I get here?" Maybe they were hoping to throw the cat.