many will indeed accept pellets , and the hikari ones seam to be taken the easiest . there is quite little variation of food intake between all the ones in the sticky , however there are two main types of snakehead , fish eaters and crustation eaters . you make a valid point and i will go back through the one i have altered (the one iam still updating ) and add the typical stomach contents found on inspection of wild caught specamins.
i personally find that most snakeheads in aquaria do very well on a mixture of pellets , shrimp , prawn , and worms as found at the local bait shop .
cheers col