Its fine to do those things (and I tutor kids too), but you should hardly get to claim that you're doing charity if you're knowingly and willingly doing far less good than you could be doing.
Lets not argue "by definition", definitions do not change reality.
Just because the future will be very different doesn't mean we can't make good predictions about it (though the one you're referring to does seem like a bad prediction). For example we might predict that AGI will be interested in preserving itself and getting resources (http://en.wikipedia.org/wiki/Instrumental_convergence).
