Why Halloween Is Much Scarier Than "GMOs"

I know many people avoid genetically modified organisms (GMOs), but I'd never heard of this. Although I am a bioscientist, I was unaware I had to avoid GMOs in the name of health, food security, and proper agriculture. According to its sponsor, the Non-GMO Project, all of October is a chance to "raise awareness about ... choosing non-genetically modified foods."

Genetically-modified food has been around for decades, and has been served trillions of times. Ninety percent of our corn was GMO in 2014. Am I missing something?