difference between Land artists work in the environment and art works by them in galleries

What I considered about the land art artists is that in order to survive financially they need to create sell-able work... so is there a difference?  

Here is two similar works by Richard Long, one outside and one inside. i'm sure its with the aid of photography but it seems to me that the way the context of the place its being exhibited certainly shows how people view it. There is a height of sophistication and snobbery with the exhibited work to the right, and with the girl running beside the work in the picture to the left there seems to be a much more freer and less specific or mannered atmosphere. after all that was what environmental art was initially designed to do.