It is sort of a community, or a community that has several substructures of communities. Any place where people share information that they might be passionate about could be considered that way. You've got generations of people now that have primarily developed their relationships with others this way, due to whatever personal circumstances they have going on. Is it smart to develop relationships where comments can be upvoted or downvoted? Likely not, since people may have tendencies towards making a psychological reward system out of it or might even derive some level of self esteem from it. It happens though.

When the same users interact with one another on a daily basis, that can provide the basis for potential friendships.