Attached Link: Big Box Mart

BUT WHY WOULD THE US IMPORT "CHICKENS" FROM ANYWHERE?

For the same reason we import VCRs, cars, toys, shoes, American flags, furniture, fruit, clothes, etc.  It's cheaper.  Americans decided long ago that cheaper is better, even at the cost of their own jobs.

Your dog is probably more at risk from eating an infected wild bird than from chicken treats.  Several cats have gotten bird flu in Europe, apparently because they ate dead wild birds.  Dogs may have a similar risk.