Only time breweries pull a snap rings is to replace a worn or broken part. I have filled and washed kegs at a brewery and have been using Sankes at home for over a year. If you were talking Hoff Stevens kegs then you would be correct but Sankes are just as sanitary as a corny if not more so as they don't leak. I have a Sanke with a 4" TC as well as the spear and it is spotless inside when I check it. The beer inside never gets a chance to dry so they clean very easily.
Two good videos on how to use Sankes on a budget.
Keg filler and washer:
https://www.youtube.com/watch?v=FDOFsKB6xnk
Cleaning process. I do the same thing with either a MKII Keg and Carboy cleaner of my Chugger pump. Hot PBW, clean water rinse, fill with Starsan. I tip it on its side and force the Starsan out with CO2. Once about half empty I invert to completely drain and purge with CO2.
https://www.youtube.com/watch?v=Bl6pxAV32t4
Mark