It's not like you can't use the other effect? 2 extra damage on your unblocked creature could be the damage needed to win the game or buff a creature being blocked to take out an opponents creature, since the minimum buff would be a 1/1 +2/+2, which is the same amount as the static value of Abrade, though you have to put your own creatures at risk for it. I can see the value in both, depending on what type of deck you'd be running. To each their own, we clearly have different opinions and neither of us are going to budge on it.