Snails eating soil?

I have a giant African snail and I saw it eating the soil and I'm kinda worried now

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I give him plenty of fresh vegetables why would he do this? Am I doing something wrong?

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Also I have been using regular soil but now I see that coconut peat seems to be a better option, and that it's cheaper, would it stop the soil eating thing? This can't be healthy right like just eat the veggies I gave you