When I see snails on the ground i have the urge to step on them just because I can and I do.
Funny, I like moving them out of harm's way and putting them somewhere safe. Makes me wonder what you'd do if you ran across one of these:
And with walking slowly towards a spider and attempting to trap it youhave a bigger chance of is escaping and then laying eggs in your ear at night or biting you later on because you were too much of a pussy to just smash it quickly.
I let the carnivorous plants in my house eat the insects (and occasional arachnids). It's more fun that way and less messy.
Plus, I went all mad scientist one day and got to remote control a spider once. That was fun.