this is how I look at it......the chickens are gonna eat bugs, I would rather be feeding them something I have a little control over.....
I have thought about this,,,,,I am sure the bugs they get out of the ground could just as easily be carrien a disease.......If I were to worry about everything out there that could be a hazard, the poor birds would never see daylight.......
Just my opinion, you have to draw the line and do your own research on what you believe to be accurate and worth the chance.
Maybe I'm overly cautious, but that's my excuse for not raising them. Crickets are supposed to be easy too, and I have to think the chickens would have a lot of fun catching them. But escapees are a lot more problematic. OTOH, I think you could sell crickets locally and make some $$, then feed the ones you don't sell to the chickens.
But crickets could carry diseases too.
What interests me most now is outdoor culturing of maggots, either house flies or soldier flies. I've seen pics of containers containing rotting meat, hoisted high in the air to keep the smell down, then the mature maggots crawl out the holes in the bottom and drop to the ground to pupate -- right in the middle of the chicken run. Poor maggots -- never knew what ate 'em!
Cheap too, on a working farm there is no shortage of free breeding stock for maggots. Should keep the overall population down to give them a more attractive breeding area than the manure.