Understood - in terms of accounts you are correct. But my point is that with a typical daily maximum of simultaneous users, 15k represents about 33%. In other words, 1 out of every 3 ships you encounter is being piloted by a machine (at the best of times).
As for your assertion that it is players the world over that are accounting for the 15k on-line number, I was in the same boat as you. My play time was typically between 4am EST and 7am (on either side of DT). It wasn't very often that I ran into another human being while playing. Sure, maybe nobody wanted to speak English with me. And maybe they were really good about running back and forth from the asteroids to the stations, or from the stations to the planets. Was your experience different?
I don't envy CCP's position on this. Most of those macros are not owned by "gold farmers", they are owned by real players who use macros to get ahead in the game. If you kill them off you're going to lose those accounts and then some. If you don't kill them off then people who don't cheat are always at a disadvantage.
Have you ever used macros in the game?