I'm sure it's something funny, but I can't understand it. "Illiterate? Write for free help." looks without typos. Is it something about the structure of the sentence? Or it's, because they suppose the illiterate can't read it? (From the Chinese point of view and, maybe, from the Japanese it's nothing unusual someone to be able to read, but not able to write. If you wonder how is that possible, I can explain you: many of the characters in Chinese and in Japanese are complicated. You can be fully capable to recognize a complicated character, to remember it, to know its meaning and even what's its pronunciation, but at the same time you can be incapable to write it.
By the way, it's a common case: Chinese and foreigners, who can read and write simplified Chinese, which is the official language in PRC, to be able to understand the traditional Chinese, which is in use in Taiwan, Macao, Hongkong and some other places around the world, where there are Chinese communities /China towns/. But they /people, who can use simplified Chinese/ can't write the traditional Chinese.)