re: Error order, they want me to return. WWTOTD

Obviously, the most honest thing to do is return them. However, keeping them isn't necessary wrong or dishonest. Returning them requires sacrifice/hassle on your part which you are not obligated to perform.

Update: They "agreed" for me to keep one of the black jerseys, and just mail back three. I think those corksuckers should let me keep two to make up for my time and effort in correcting their goof. Oh well ....