Old Gregg is a Deep One Hybrid?

While making Old Gregg quotes this morning to torment my girlfriend, it hit me. Old Gregg is a Deep One Hybrid!
Or...
Maybe Hastur is just a myth, it's actually Old Gregg that lurks below Lake Hali.
Suddenly it all makes sense...

If you can somehow defeat Old Gregg, his treasure consists of:
Pink Tutu
Weird Purple Egg
Life time supply of Baileys
Many waters colors of Old Gregg and Baileys
Stuffed trophy of Curly Jefferson
Living Alien artifact, "The Funk"