Interesting. What time of year did you do this? It makes sense, since at a certain point in their grubs' development the adults are busy hunting meat for them. But I didn't know they would gorge themselves to the point they couldn't fly. Something about raw, funky pork in particular?

Or maybe not. The bottle traps I built got pretty ripe when the first dead hornets started to decompose. And yet they kept coming in. Maybe the funky smell was part of what made it attractive.