This occurs in both Survival and Creative.

What Happened: Non-matching enchantments like armor enchantments are mixed with fishing enchantments on books and then can be attached to enchantable items.

For instance in Untitled.png, that enchanted book could go on a pickaxe or a piece of armor.

What I expected: Enchanted books with combo enchantments will match their expected equipment allowed list of enchanments. Looting for swords, Lure for fishing pole, etc.