I think "exploitation" is the wrong word to be used. I'm not vegan, so I really have no bearing on this, but exploitation doesn't equal harm.

This post for example is about bees. They're being exploited (in that we're using them to get resources), but is it harmful? I have trouble saying yes. It seems somewhat ideal for them. They get to go about their lives like normal, though usually in a place with a lot of flowering plants, and they get taken care of. Occasionally honey is gathered from them, but this doesn't actually harm any bees.

I think vegans follow dogma too much. They should consider their reasons for themselves, and consider what food sources fall into that. The dogma is useful for quick communication and sharing of information, but I would suspect honey farming is a lot better for the living things involved than even a lot of plant farming, which requires large swathes of land to be dedicated to farming, which certainly isn't good for native species and arguably plants can feel too.