Worker bees, throw off your chains!
How can bees not be eating vegan? All they do is gather pollen and nectar, both plant products. Then they do some magic bee stuff and make honey out of it, which they eat. So if you sit down to share some honey with some bees, how can they be eating vegan and you're not? If they're getting the honey from the crops humans planted and tend, wouldn't that make bees dependent on farmers and mean that vegan bees can't eat nectar because it's a human product? Wouldn't this line of logic mean that vegans can't eat food produced by other vegans because an animal (a hominid) was involved in its production?
Again, I don't contend the arbitrariness of the boundary, and I honestly can't tell if you're being serious, but, as I said before, veganism is about not using any animal product. Honey is the product of bees, pearls are the products of oysters, wool is the product of sheep. Sure, your human example points out the arbitrary nature of the philosophy, but again, if you step back and take a look at your own moral and ethical choices, I believe you'll find your lines to be just as arbitrary, and I'm sure there are many out there who could as easily mock them as you do those of vegans.