ShaneLeeder is correct in saying that it's just a name, that's true, but they may be adding "the" to the name to help indicate that their shop is special. "the" is used with superlatives like "the biggest/the smallest" so passively when they're saying "THE woodcraft shop" they may be pointing out the special nature of their shop or are implying "THE (best) woodcraft shop" or "THE (only) woodcraft shop (in town)"