I put mine far away from the plants, normally by the fence where I know they won't get squished underfoot and may find some grass to chew on. Knowing full well they will be back in a couple of hours for more....sigh
Don't really have a snail problem but slugs get trodden on.
The Telegraph had a slug nematode 'recipe' where you put them all in a bucket with some water and some food, covered it to stop them getting out for a couple of weeks and let them form a nematode soup until they all die from bacterial infection. Then you strain the lumps and bodies out, water down the results and put it on your garden to kill more slugs. Sounds perfect...
I save marg tubs, go on a slug/ snail hunt and pop them all in the tub together. I call it the tub of death. I leave the tub in the garden until it gets too full or smells too "deathy" then put it in the general waste bin. It is cruel but I don't have to watch them die.