Vanos, I only put the crab, snails etc as that is what many claim they will do. If they can catch it they will eat it. I have had my star now for 1 month, I do spot feed with krill, shrimp pellets etc. They will also search out food on the sand floor too. I have a snail, hermit crab, mushrooms and knock on wood he has not bothered to eat them. I have seen him climbing all over my rock and has not touch a mushroom yet..... :cheer:
I personally do believe though that in the aquarium we must feed our inverts. If you just let them forge on what falls and not supplement them they will waste away, eat things they should not etc.
The home aquarium is not like the ocean, so in these tiny quarters of saltwater all inverts have to compete for food to sufice their hunger. If you are spot feeding that is great, maybe your snail was dead I don't know.
Good luck to you...... :happyfish