This book was excellent for helping me learn Haskell, but the gendered language and fat-shaming jokes made me feel very uncomfortable, eg: "You're fat! Lose some weight, fatty!","You're supposedly normal. Pffft, I bet you're ugly!" and "You're a whale, congratulations!", "Sure, we could just type them all out but obviously that's not a solution for gentlemen who demand excellence from their programming languages."
Clearly the author is going for a casual, conversational, jocular attitude. That's part of what makes LYAH so approachable. If you want dry, sanitized, bowdlerized instruction, LYAH is not the place to look.
I think it's unlikely that he was trying to be malicious and is probably just not sensitive to what it's like to be on the receiving end of some of his examples.