please describe the reason for the neutral boxes in the free throw lane.

Are you talking about the top two spots being open or why players can't stand on the boxes?

These are encoded signals to aliens informing them when their messenger on earth, Ron Artest, is going to call them down to throw beer at Dick Vitale. It's kind of like crop circles.

Damn, where's those meds?

I believe he is referring to the "blocks". Is the question why they are different in size than the other lane space markers?