Why is there a Kosher U on Bacon Cheddar Pretzel Pieces?

Bacon is not Kosher. Kosher U on that specific product means that it has been certified as kosher by the Union of Orthodox Jewish Congregations of America. The certification means that the product does not contain any ingredients that are forbidden by Jewish dietary law, and that the product has been produced in a manner that meets the requirements of Jewish law.

In this case, the Bacon Cheddar Pretzel Pieces may contain the words 'Bacon Cheddar' on the packaging, but they do not contain any actual bacon, therefore allowing the U Kosher to be on its label.