The J-1 visa, on the other hand, strictly prohibits using visa-holders to fill a labor need or engage in work that a U.S. worker could be hired for. In theory, these visas are supposed to provide educational work and study opportunities, and are often awarded to visiting professors and scholars.

Ive yet to ever hear of any J1 visa used that way at all. Theyre almost exclusively used to fill labor needs, especially in hospitality and service