Well, the reason(s) there are opinions are to find out what people are doing for a humane way of prekilling.
Give it enough time, and enough people talking non-chalantly about "how it's just a rat", etc.... and it will become an issue. Trust me, I own a pet store, and I get animal rights people in all the time. Lord forbid I have a hamster that was killed and partially eaten before I see it. We had a lady several months ago try to shut us down because we had a half eaten hamster in one of our cages.
Rodents eat rodents sometimes, what can you say?
It won't be much longer before they change the AWA laws and we'll all be criminals for feeding off rodents... As for now, rodents and fish are not covered under any law, and technically, you can do what ever you want to them. Not for the lack of ASPCA trying. You can see them coming, and I've had to literally run them out of my store before...
So, please for the good of all animal lovers and keepers out there, don't spread bad info on pre-killing and all that good stuff. It will come back to haunt all of us one day.