I'm not even suggesting that people don't buy the 3rd party games because they don't get points, but I am suggesting that more loyalist will actively seek out extra 3rd party titles because they do get points.
The majority of us may just keep buying what were were already gonna buy (1st & 3rd party), but maybe we will put more effort into making sure we buy it new since we actually get something out of it.
And when it comes down to buying a game for those few extra points needed to reach Gold or Platinum for the year, we now have the option of buying that 3rd party game we always meant to try out but never got around to buying vs picking up the first cheap Nintendo published software (such as Fling smash or something else equally low profile)