Was the Gutenburg Press Stolen?

I read an interesting paper somewhere a while back that I just now remembered. Ok, so it isn't really related to grimoires at all, but hey, it's my blog after all. Anyway, the article said that the original idea for the printing press was, in fact, stolen! Too bad they hadn't invented patents back then. The story goes that the printing press was not in fact invented by Johann Gutenburg, but rather a Dutch woodworker named Laurens Coster. Laurens came across a birch tree while out in the forest looking for wood and decided to carve some letters out of the bark to take to his children. He wrapped them in his handkerchief and started for home. When he arrived, he saw that the sap had stained the handkerchief, which gave him a brilliant idea: using blocks of wood to create type. However, after he began working, someone caught wind of the idea and stole the supplies while Laurens was at Mass. He sold the idea and supplies to Johann Gutenburg, who then decided that using metal would be more practical and durable than wood. And of course, the rest is history.
Now, allow me to state that I do not know if this story is true. But, true or not, it is an interesting story. Of course, it wouldn't surprise me if the story were true, but I noticed something that was a bit off. How could a woodcutter in the 1400s have been literate? In general, only nobility were taught to read and write during that time. I suppose he could have been taught the alphabet by a customer if he was commissioned to create an alphabet board for some noble children, but other than that I don't see how. In any case, it is a lovely, wonderful story.

Meren heart,
Nefabit :3