Yeah, I think since being literate is such a common thing, people honestly don't entirely understand what being illiterate means from a practical standpoint. There are plenty of people that legit can't read, but still have enough personal context to know what some text actually means, just from their own experiences. So, using Mick Foley's example, Abdullah could've easily gotten enough context to know what a club sandwich looks like on a menu, and order it because that's something he likes, but couldn't read the description of what's on it.
Also, on Hannibal, fukk that piece of shyt. He was just as grimy as he was describing Abdullah as being, and for someone who made a career out of doing those bloodbath matches, it's crazy that he had Abdullah out there blading him in matches.