Evil predators in the garden

[piroska]

They bloody don't. 

SLugs and snails not only provide food for various other creatures, without which, they would have a serious problem, slugs also eat small invertebrates.

Snails are primarily decomposers that feed on dead leaves and flowers, speeding up the recycling of plant nutrients. Their feces fertilizes the soil much more quickly than bacteria breaks down plant material. When snails die, the decomposition of their shells slowly adds calcium to the soil.