Technically this is probably true. But only because I'm not likely to look.

Not replying to Ritalin because he argues misleadingly and with sockpuppets about literary matters, but I've read a great deal of Japanese literature and it never occurred to me that there was no sarcasm in it, and quite the opposite (especially in satirical or humorous works, as one would expect, like I Am a Cat). Heck, they do sarcasm just with the honorifics - switching from a normal -kun or -san to -sama, or worse, -dono/-tono. (If one doesn't like literature, one won't have to go long in watching anime to spot sarcasm; KyoAni seems to have a lot of sarcastic male protagonists...)