I'm staying at my mum and dad's in Somerset and we too have just noticed this phenomenon today. Bizarre! And that's how I ended up on here, looking for answers. So many wasps and large blue bottle type flies. They appear to be licking the leaves and don't seem bothered by me, except when I walk past the Bay quickly, they all swarm and then get back to business on the plant once I've passed. Most odd, but I think the honey dew answer is the most likely. No signs of aphids at all. Lots of ants, which are probably after the same sticky sweet coating.