Yet the 9's average 17-3 or 16-4 when playing anyone other than a 9. And you think they should spot LESS? The only reason they don't spot more is because it would lengthen the matches. Lesser rated, but sporty, players can go up, too. Besides, if you have someone on your team who is likely to win a lot of matches with big scores, doesn't it make sense in some way that you should have to put someone on your team who is likely to lose a lot of matches? Isn't that what a handicap system is supposed to do? Handicap you?
The difference between that and 8-Ball is that even the best 7's in 8-Ball lose a game here and there so they don't average 80% PA or higher like the 9's in 9-Ball.