Catfish may show some interest in plastic or fake worms but they are unlikely to eat them as they are not a natural part of their diet. Catfish are opportunistic feeders, which means they will eat a variety of food items that are available to them in their environment. However, worms, grubs, maggots, and other types of worms are natural food sources for catfish, that's why they are commonly used as bait. Plastic or fake worms will not have the same scent or texture as real worms, which are important factors to attract catfish. Therefore, it's unlikely that catfish would bite or eat a plastic or fake worm. It's also important to note that fishing with plastic or fake worms is not recommended as they can be harmful to the environment, they can be mistaken as food by other animals and end up causing harm to them.