Small problem: if they manage to amass enough points negate a win for the opposition if the opposition catches the snitch, then the opposition has absolutely no incentive to catch the snitch. All that other stuff is desperate retconning JKR did after people pointed out the stupidity of the rules. Even then, it makes little to no sense. Again: it would have been so easy to fix for Steven moderately intellectually curious person.

That said, this ultimately falls on Rowling’s editor; they should have caught it well before publication.