It's because the hard fork took effect for all posts, which haven't yet been paid out (i.e. not older than seven days), effectively making everyone richer and more inclined to cash out.

Yes, you are right that the amount remains the same and my suggestion was to spread it out between all authors, by investing more voting power in lower paying articles we like and less voting power in articles, which are already paid well (say, in the hundreds of dollars).

Why? Well, the less cash each user gets, the more he we will wait before exchanging for BTC and then for fiat money. This will increase the time we have until the next money laundering (which will increase the price of Steem again). If there's no next money laundering, Steem will gracefully decrease in value (as opposed to high price drops, if well paid users cash out all at once).

That's the theory, at least :)