The Boston Marathon, an annual tradition since 1897, rightfully attracts its very own superfans — many of whom show up to the course hours in advance, no matter the weather, to root for their favorite runners with enthusiastic cheers and homemade signs.

I haven’t thought about my days as a fangirl for a long time. This morning, however, while browsing Twitter, a picture caught my eye. It was a single chicken nugget, lying deserted on an asphalt road....