Yeah, that's not necessarily true. Even a dragonet that eats mysis will continue to hunt all day long. I don't think you can assume that a scooter will get enough calories from a once-daily feeding of frozen foods, especially in a smaller newer tank. Dragonets that eat prepared foods are likely getting enough to supplement its natural feeding behaviors.
To the OP, how big is your tank? Do you have a refugium? If the tank is a decent size, well established, and doesn't have any major competition for pods (some wrasses, for example), you may have a sufficient pod population that it'll be ok.