Mine were like that with yogurt until I dipped my finger into it and made a fuss about how GOOD it was.I found that some foods just take repeated exposure to, before they think of it as food. Do they like mealworms? If so, maybe mix a few smaller earthworms in with a few mealworms. Anyway, they are all individuals with their own preferences, but I suspect as they get older, they'll try them.
Now I’m not saying (lol) eat some worms. But townchicks
Has a good point, keep offering them. Who knows.





I will only do that for initial introduction if they don't get it. But I have sooo many birds, someone usually bust's out with a hilarious game of "keep the worm (or whatever) away, flag football". And the chase ensues. 
