I have no problem with people killing venomous snakes on their own property.
Property owners have a right to protect their loved ones or friends that may be wandering the property.
I've killed a few rattlers on family land in Texas. I didn't take glee in it though. It was just a thing that had to be done because my 4 & 5 year old loved playing outside.
Taking pleasure in killing, though, makes you a pretty low IQ individual in my opinion.