Wow, the bait approach makes great sense. The OP's right, those little nasties will be attracted from a long way off. I used to have to take the grill grease out to the reeking grease tank when I worked in fast food in college and there were clouds of them out there. Chowing down on waste burgers and drink syrup bladders in the dumpsters too.
Amen! In fact, any thin solvent will poison/drown insects very quickly - the thinner and lower the surface tension, the better. One of my favorites is CRC Electro-motive cleaner which is non-flammable. Used it to go cockroach hunting every morning back when my apartment kitchen was infested. When I turned the light on, the place would come alive with them scrambling to get away. Very effective. Starter fluid is good, works fast. A co-worker once gave me a gas can full of last year's methanol dragster fuel - works great! That said, the down side to most of these is fumes/flammability/ventilation and that they may affect painted surfaces or vinyl siding rather badly, so watch out there. I used engine cleaner or something I grabbed off the rack in a light fixture with a huge paper wasp nest in it and it killed all 20 or so in seconds. They didn't even try to fly - just fell straight down and barely moved. Trouble was, the paint turned rubbery for some time. It's still there, but it doesn't look like it used to. . . .Carburetor cleaner (spray can) kills bees on contact. As soon as the mist hits them, they drop dead
I often wondered what a scoop of dry ice chips or some liquid nitrogen would do if poured into a yellow jacket burrow. No ground contamination with chemicals and the cold gas would displace all the oxygen for the ones which aren't just frozen solid trying to get out. I never had ready access to such exotic materials, but it's an interesting idea.