In 1920, Mattraw worked in management but was also the proprietor of a delicatessen in New York. He and his family maintained the residence on Winslow until moving to California. Mattraw would appear in several uncredited silent film roles including The Thief of Bagdad (1924) and The Red Mill (1927). He would go on to work for a variety of film studios, including Universal, Warner Brothers, Fox, and many more–even appearing in the Stan Laurel and Oliver Hardy film, Babes in Toyland (1934), as the uncredited Town Crier. After taking on more uncredited roles for Fox, including George White’s 1935 Scandals (1935) and Wee Willie Winkie (1937), he executed the uncredited role of Bashful in Snow White and the Seven Dwarfs (1937). In the film, his character is kind-hearted and, moreover, incredibly shy–as evidenced by his flushed face and knack for twisting his beard into knots when embarrassed. Mattraw went on to appear in films for Fox, such as In Old Chicago (1937) as the Beef King and The Grapes of Wrath (1940) as an uncredited migrant.