I agree pithing is not easy. It is effective if done correctly. I also suggest that C02 not being a good way and freezing a reptile a very poor choice. I feel that if a person is breeding snakes (anything actually) they should be prepared for this possibility. It is a real chance and is likely to occur sooner or later. It is part of the responsibility of breeding if a person cannot bring them selves they should not be breeding at all.
I think it is different for a pet owner it is not as likely to expect an emergency euthanasia to happen and they can be excused if the choice is die from server trauma over days or a freezer over hours, freezer wins. The first choice is clear, pithing or vet but a pet owner didn't exactly sign up for pithing. A breeder does.