combination of the words "snack" and "activity." Snacktivity is the action of snacking as an activity. It can involve any foods which one considers a snack. Also, it can be a combination of snacks that can perhaps form a well balanced lunch, or brunch.
"Don't forget to bring some baby carrots for snacktivity!" or "yes its time for snacktivity!"
A gathering of people centered on a fun-to-eat food, such as lobster, fondue, and, to a lesser extent, oreo cookies and string cheese, where the time, physical rigors, and mental exertion required to actually eat the food negates much of the caloric load.