When I shall be dead, the principles of which I am composed will still perform their part in the universe, and will be equally useful in the grand fabric, as when they composed this individual creature. The difference to the whole will be no greater betwixt my being in a chamber and in the open air. The one change is of more importance to me than the other; but not more so to the universe.
My hunch is that people often affiliate with causes online for selfish and narcissistic purposes. Sometimes, it may be as simple as trying to impress their online friends, and once you have fashioned that identity, there is very little reason to actually do anything else.