What I like about all of the work from Lartigue that I have seen, is that it succeeds so wonderfully at being both an interesting/amusing artistic expression (to me it seems like poetry), while at the same time being a truly revealing "documentary" glimpse of the times that he lived in and of the social class he lived in. It is obvious that he was not worried about the mundane details of how to pay his bills because there is so much playfulness and beauty in his images. This might be because he was well off, financially, or just because he was playful and carefree by nature. I prefer to think the latter (for no real reason). It makes me think of Doisneau who also worked in Paris but a little bit later than Lartigue. The other important difference is of course that Doisneau was a professional photojournalist who very much needed to keep the bills paid. But still, when you look at lots of his work you see a real sense of humour and love of life. The difference is that the world of Doisneau is working class, and the world of Lartigue is aristocratic. To find someone with the skills and motivation of Doisneau in the working class is to be expected, really. But, to find someone like that in the aristocratic world is unique. That could be a whole other discussion itself.
The thing that matters, I think, is that all of these people succeeded so well at giving us a "window" on their world. I am including the work of Lee Friedlander here, which is actually discussed in a separate thread. The thing is that many people have said they do not find the Friedlander stuff to be artistically interesting, or something like that. Well, fair enough, but you can not deny that he susseeded in showing us what his world was like - not just what it looked like, but what it looked like to him - and perhaps his "poetic vision" is just not as appealing to many people as that of Lartigue.