The world is not fair. I dont think 10 or 12 is that bad for high school soccer.
There are also different ways than scoring goals to humilate your enemy. If you are up 9 or 10 already why not play possesion of play a game of nutmeg vs your opponent. This will keep the score level down and you skill level at top notch. But it will prolly make them still feel bad, cant really avoid that.