Even though I heard it was supposed to be German-Catholic background, there’s only one thing German — they say ‘please’ for the more common ‘pardon me’, which comes from bitte.
“…He explained in broken English that one of his daughters was ill and he probably could not be there. I did not understand all that he said, so asked, ‘Please?’ per Cincinnati custom. ‘There is no need to plead. I will be there if she is feeling better,’ he replied.”
1998: Jose I. Sarasua, "Come to Cincinnati... Please?", Cost Engineering, volume 40, issue 5, 5 May 1998, page 9 http://connection.ebscohost.com/c/editorials/664754/come-cincinnati-please
Cincinnati are some of the most polite persons I have ever met in the US. When asking someone a question, instead of saying “Excuse me,” or “Pardon,” they say “Please?”
2001: Jeff Robinson, "Say what?", Ohio Magazine, April 2001, page 77 http://lrc.ohio.edu/lrcmedia/Streaming/lingCALL/ling270/saywhat.pdf?page=2
By the same token, one contestant who doesn’t hear a particular question could say “Pardon me?” while another could say “Please?” Again, neither would be lying if he said he was from Ohio.
In Maine, where as much as a quarter of the population has French ancestry, you may hear a stray hair called a couette, and in parts of Ohio please is used in the same way as the German bitte, to invite a person to repeat something just said – apparently a remnant of the bilingual schooling once available in Cincinnati.
2011: Ellen McIntyre, Nancy Hulan, Vicky Layne, Reading Instruction for Diverse Classrooms: Research-Based, Culturally Responsive Practice, Guilford Press, ISBN 1609180569, page 72 //books.google.com/books?id=m7BAOCj8mHQC&pg=PA72
Ellen grew up outside of Cincinnati and believed her own talk was the “norm,” while others were speakers of dialects. She was in graduate school before she learned that not all people say, Please? to mean Can you repeat that?