Thanks everyone. I would have the dogs eat the same food if I had anything to do with it haha. Alfie's still on puppy food. But my roommate feeds her dog Iams

. I would love to convince her to switch to a better food. Hopefully by the time Alfie switches to regular dog food, she'll be convinced. I have several months to do the convincing.
In the meantime, I will be more diligent on keeping Alfie's crate (where his food is kept) closed when I'm not around.
It's weird though, the other dog only goes for the food when my roommate is home. He never goes after it when she's gone and I'm there. When we're both there, he'll go after the food. It's almost like he knows mommy most likely won't be paying attention and he can get away with all sorts of things when she's around. Roomie gets in a zone and blocks everything out. I'm just the kind of person that is aware of everything going on. Does this make any sense? I'm rambling. I'll be quiet now lol