Might have been an ashcan or a promotional giveaway.
Library of Congress record:
On sale date from the publication date found in the Catalog of Copyright Entries, Part 2, Periodicals, New Series, Volume 34, 1939, Number 4. Class B periodical. Copyright number B 432170.
Champion comics,© Worth pub. co.,inc.
v. A, 1939, no.
1, Oct. © Aug. 1; B 422614.
Volume is A then issue number 1. August 1st is the publication date, "B" refers to it being a second class periodical.