I had a similar experience this morning. A whole procession of dogs came past. Most of them rummaging through my gear. Some of them were quite aggressive large dogs barking and jumping up on me. They weren't under control at all.
One of the owners wasn't much better. I was told to 'tidy up' my gear, Then she had another go on the way back 'I couldn't have picked a worse place to leave my gear' , being near the access path (I'm not sure what difference that made with dogs all up and down the beach and given that they all made a bee line for me).
I don't think dogs should be unleashed at a popular public place like a beach.