I agree.I Never kill them just run away. Because i know that they are 1 hit. It's a waste of PP.
I have to admit, there is something satisfying about it.
For example, you know that Abra you try catching in the beginning but you can't because it likes to ****ing teleport away all the damned timed? Feels so good to come back later and just beat it's face in saying, "WHERE'S YOUR TELEPORTATION ABILITIES NOW?!?!?!?!?!" XD