Arrows of strength double in stack size when picking up

While playing around with the new arrows, I discovered that when in survival mode, if you shoot an arrow of strength and pick it up, it gives you about twice as many arrows that are in the stack that you shot from.

Example:

I shoot one arrow from a stack of 64. Pick it up and the stack doubles in my inventory.

NOTICE: I have not tried this with other arrows, but I assume it works the same way.