Caffeinated Bees

Interesting goings-on at the compost heap the other day, with the honeybees frenetically gathering coffee grounds in their pollen baskets. Not sure what was up with that, but the proof is posted below for all to see.
Given the dearth of pollen sources so early in the season up in the Northern Catskills, perhaps the bees were simply "taking what they could get" by gleaning the coffee from our discarded Melitta filters. I wonder what, if any, merit the grounds have from a nutritional perspective.

Or perhaps these bees (and, one can only hope, bees across the world) are hyping themselves up for a long overdue battle with homo sapiens for world dominance. If so, I'm rooting for the bees and will gladly serve as barista to the revolution.

What interesting or unexpected things have you observed honeybees gathering or doing of late?