OMG, I have those too, never seen them before. Not just on BWs but all the tomatoes, not too many of them (not swarming) but they don't seem to have a preference. I think the damage on my hybrids is from flea beetles (I can see those too and the holes are too tiny I think for this bug) but some of the damage is pretty bad.

Looks like a bird dropping but when you flick it off you can see it spreads its wings like a beetle and the body is yellow under the wings/carapace?

Tortoise beetles. Their preferred food is morning glory, including the wild bindweed. If they were feeding on your tomaotes you would see holes, so likely they are passing through on their way to find a real food source. AJs, bugs are usually pretty specific about what they eat, so I would look real close to see if any of the bettels are actually chewing the plants. They do make holes about the size of themselves in morning glory leaves.

Bind weed I've got! Strange thing is, I had been seeing these occasionally on the potted tomatoes as I was hardening them off near the house (still have some bindweed I pull out of the garden, I don't know where it comes from since I haven't noticed it in the lawn - that's a combo of knotweed, crabgrass, and clover LOL). I'll look for larger holes, but mostly my hybrids (some OP varieties) have FB damage with brown tissue around the shotgun holes. I've never noticed brown dead tissue around holes in brassicas, but I read that it's a different species of FB that attacks nightshade family.

Overall a very buggy year - lots of spiders too, I don't mind them outside but don't like them in the house or the cars.