Saw my SiL yesterday at a family gathering here in Southern California and she told me this awesome story.

My SIL is a teacher in Pasadena and once a week an adaptive PE teacher would come in and do some PE for her class. My SIL is a special needs teacher so PE is a very generous term.
The PE teacher is a typical female PE teacher and always wearing large over sized hoodies. One day the PE teacher comes in with a royal blue BYU sweater. My SIL is so confused as this PE teacher has a very heavy east coast accent and often wears a Star of David necklace. My SIL, a BYU grad, goes up to her and asks about the BYU sweater and the PE teacher says her son is a QB on the BYU football team, Jake Retzlaff.

This all took place a couple years ago so way before the boom in popularity that Jake experienced this year, but still pretty cool.
From what I hear his mom is almost exclusively wearing BYU sweaters nowadays at elementary schools across Southern California