Because that is a regular day's operation. What draws attention is the use of satoshi's wallet as a destination

This exactly. Whatever the motive, whomever fully realizes that this address is watched with a very fine tooth comb and simply isn't possible to go unnoticed.

Why the expenditure? Someone above basically said marketing -- marketing Bitcoin so headlines hit the masses and maybe get some sort of ball rolling again. I think it's safe to assume there is a larger plan in the works and whomever responsible has played their hand and now hopes the cards fall as they projected, for whatever ends.