It's not worth it unless you personally like pet rats to begin with, like a fun side hobby. It barely saves any money per month compared to buying frozen in bulk. They smell, take up room, and require cost of care and food, time and effort. A LOT more care and time than snakes do.
I remember seeing someone post that they breed the fancy desirable variations in coats for rats, and breed for good temperament, so they end up selling the quality ones as pets for up to $30 or $50 per rat! And then save some others for food. That's nice, but you gotta love rats lol.