There are no dumb questions!
Crabs have funny appetites. They eat more or less at different times in their moult cycles, and will often like something one day and not the next.
Low temperatures can affect appetite because their metabolisms are tied to temperature. At 80° these crabs tend to become more active & will often eat more.
Also, studies involving Es (C. compressus) found that they don't like eating the same thing twice in a row, and from what I've observed in my PPs, I'd say they're the same in their attitude towards food.
Providing variety is key. Animal proteins, fats, nuts & seeds, dried leaf litter, wood & bark, fruit & veg, and chitin (from insects) are all important.
The page I'm linking to below is a great read about creating a healthy hermit crab diet:
viewtopic.php?f=25&t=92554
In the food & water section you'll notice the safe & unsafe food lists too.
Commercial diets are frowned upon not so much because crabs dislike them (although no crab wants to live on just pellets) as because many are nutritionally 'meh', and/or they contain preservatives believed to be harmful to invertibrates. (Even if a preservative isn't immediately harmful to a crab, there's the risk if it accumulating in the bodies of these long-lived critters & causing illness later, rather like carcinogens in humans.)
Finally, sometimes they are eating, just they're taking teeny pinches of what's offered, and not dragging it off into burrows, or traipsing through their food dish. Enjoy this while it lasts - eventually you will have to hunt for a hidden piece of shrimp or fish, and in an 80°, humid crabitat... well, its a memorable smell.
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