Here's what you should give a shot. My local pet store was doing this and it put a knot in my stomach. I bought a critter keeper dry ice a Rubbermaid and printed up the instructional from this site and physically brought it to them and showed the owner and workers the proper way to do it and left the supplies with them. I came back a month later and they were still using the correct method! 12 dollars out of my pockets and hundred on small animals no longer suffer. Try that, if they are given all the tools needed for t to be done right there are no excuses. They may change....
You know what... I might have to try this. Or at least contact them and tell them how I feel about this issue. If enough people speak up they might change.