Ah, OK... Thanks for the explanation.
I think the reason for giving a quick reply is often just to say that they saw the response and appreciate it, but don't have anything more to add to it. I know that if someone gets hundreds of replies each day it would take far too much time to write several paragraphs of response to each. I don't expect authors to spend all their time on responses. However, once the author gets their vote-slider, I don't see why they can't give a small up-vote to their fans. (Anyone without a vote-slider is forced to give a 100% up-vote and thus only can give 10 per day or lose their ability to control their vote power.