well from what I have read here and other places you can feed a dragon other things than live bugs.
it's just that they take to live ccrikets so well and they are good for them to eat.
a dragon is an "Omnivore" so they can eat a wide array of foods.
as long as they get the right amounts of the proper "stuff" as in protine, vitamins, minerals etc.... they will be fine.
now this is not a "diet guide" but just to give you some ideas on things that have been given and are ok at least some of the time:
small portions of cooked fat free chicken meat, cut up to small bites.
canned and dry dog food
there are somme things to watch out for... some dog food may have soy meal, this has elements that can/will block calcium processing so no soy!
when a dragon is young (hatchling to 4-6 months old) is is more of a "Meat Eater" and is more interested in moving food items.
this is logical and should be allowed as this is the "pre programming" of nature.... they need to move and eat a lot for 4-6 months in the wild to get big enough for other dragons and critters ( birds, other reptiles and so on) to not see them as a "Quick Snack" 
so if you get a 1-3 month old figure you need to give him/her at least 2-4 months to "Bulk Up" and get as big as he can
Example: My DB was about 4" long when I got him, I have had him for 6 months and I figure he was maby 1 month old when I got him
today he is just shy of 17" long, about 11.5 Oz / 300 Grams
and is now happy with mixes of salad and stuff...
but for the first 3 months it was live bugs all the way....
you might say he's 12" of transformed crickets!

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