I do cache together with others on a regular basis, but I don't do it in the same constellation every time and I cache quite a lot alone as well. I think that's true for the majority of people.
I don't see what would be the object here. Showing stats based of the union of caches that people in the team have logged? Or the intersection of caches logged? Or the intersection of caches logged, where the logs are on the same day? Or something else completely?
In all, I don't think this is a feature that would be possible to construct in a way that is both usable and understandable.
