You seem to know a lot about Keira and how she spends her time, is there something you're not telling us?
And I don't remember suggesting that Keira should reply to every fanmail she gets, that would be mental. Half of them would be from hormonal teenage boys telling her how much they want a shag.
Obviously the mail doesn't go straight to Keira, so maybe the people who read it first chuck away the crap ones and maybe pass some of the more meaningful ones to Keira.
It's called hope
. I'm not for one second suggesting that it's her responsibilty, I'm just trying to build up a realistic argument for why she would reply to some of them.
Otherwise what's the point in writing her unless you want an autograph (which might not even be hers)
How about being a bit optimistic?