My pet theory is that Ozzy Osbourne is actually in regular contact with aliens and frequently travels with them on a time paradox way, decades for him, just days on earth. Thus his confusion is genuine, he really doesn't know what planet he is on and his mind is more filled with alien customs than humans. Also, that is why he acts like such an old person, his body is old but his mind is even older.
Definitely it wasn't the drugs, no sire.