I do it many times :( there are so many, frog however I´ve never hurt. I love them.
slugs spread disieses so that´s why I´ve killed them. A small child once ate one playing and she died. they are dangerous to small children. and I have a 4 year old niece. so yes I kill them with a lot of salt.
I lthink the only way to know how they must feel is if like you spread salt in an open wound, just that instead a of wound its in the whole body, that´s why they die.
edit: I don´t enjoy it, but they are dangerous, just like roaches, flies, and rats. I don´t kill anything else