From what I remember from old an interview, yes, Hy Pro Glo is a brand of dog food. However, Charlie didn't remember that when he thought of the title. He used it to describe that glossy, dead look in someone's eyes when they're on drugs. Then when he saw the commercial on TV....... Doh!!!
SSC is Suck Some CocK???? I always thought (don't know if it's true or if I made it up) that it was Spit'z Sitar Crap. Hmmmmmmm...