Things that go slime in the night

WARNING.
This post mentions the killing of snails and slugs. Do not read if this is not your cup of tea.

I have always loved snails. They are such sweet looking little creatures. The babies are adorable. I have never worried too much about them or slugs, but I have also never been really serious about my gardening either. I am now stuck in a quandary. We have a lot of them here. A lot of slugs too and they are doing a lot of damage. I have started to become quite ruthless in my eradication of them.
A hunt them at night with a torch. The array of slugs we have here is amazing. All different colours and sizes. Some so large I mistook one for a snake at first glance. I do not want to use baits here so I have taken to hand picking them off. I squash the slugs without a second thought, but I have trouble killing the snails. I have taken to tossing them into the vacant block next door. I don't know what this does to be honest. They probably make their way back or maybe the fall kills them or only maims them. My sister mentioned collecting them and freezing them, I think hubby would have issue with me having them in the freezer. Would drowning them in water be an acceptable method?
My other concern is that maybe killing them is somehow unbalancing my ecosystem here. Could that happen? I have noticed them feeding on things like fallen rose petals etc. If only they stuck to those instead of feeding on my brand new seedlings or strawberries! There jut seems to be so many here. I have collected 100 at a time. They do extensive damage to my Hippeastrums and Aloe Vera. Is there a way to live in harmony with these little beasts?