No, I don’t think so. I think it’s about the people relaxing. The boat tells you it’s a river, which might not otherwise be obvious, but its just fortuitous really.
In The Europeans a few of HCB’s photos on this theme are captioned ‘First paid holidays’. I’m away from home so I can’t check whether this one is so captioned. But it’s hard for us today to comprehend what a big step in social history that provision was, and how recent.
I see what you mean about the historical and social importance.
Personally, I feel like everything in the frame should contribute to the image itself otherwise it could very well be removed without changing the work.
Here the boat, the people, the wine, they set the scene but they don’t really transform it. If HCB wanted to document the first paid holidays and giving us the feeling of "presence" and of being there to see it and being part of it, he nailed it sure.
But as a photograph that stands on its own as art or relate to the passion of geometry of HCB, I don’t feel it has the same visual poetry or impact.
P.S. I just checked my HCB book "The Europeans" it is indeed been titled "The first paid holidays"