I don't want the game limited to only good interactions or the right thing to do at all... I would be bored to tears if I only watched movies like that or read stories like that.
With MFP.. yes you can let them live in filth .. the consequences are a filthy uncomfortable home for your sim.. that is very noticeable.. and an undying rodent (except from age) that bites ... and of course a disease that will kill your sim and can spread and kill others if you don't cure them.
I have a hamster in a few homes that are well taken care of... immediate cleaning of the cages by good responsible sims one (Stardew Valley Abigal)... and I have evil types of sims (Sims 2 Loki Beaker types) that want to spread disease on purpose for his own deviant experimental reasons.
I've personally never harmed a hamster or pet in real life and don't plan on starting any time soon. Really.. It's a game not everyone likes to play out Mary Sue over and over. You can take care of your hamsters responsibly.
