LOL, what's with the 3rd degree, you guys with the EPA, or something ?
The place I use has a large tank in back, that they seemed to allow a variety of liquids in (I'm thinking there may have even been 2 different containers, but I'm not 100% on that, and don;t recall any specifics). Last time I was there (maybe a month or so ago), they didn't allow you to go in back anymore, or pour it into the tank yourself, they took your container from you at the counter.