CP's have the FAR better deal than NCP's. And a lot more "rights" too. My fiance/common-law husband is the custodial Dad to his son. He had to struggle, scrimp and save just to get by feeding and clothing his son without support from Mom. We had to get by with a tiny, 700 square foot house, old junky cars and no vacations to be able to support him. We rarely got any "breaks" from parenting, because Mom rarely exercised her visitation rights.
I wouldn't trade it for the world, and he's not even my blood. We got to be there for every "first", we got to go to all those choir concerts, baseball games, basketball games, conferences, school plays, etc. We got to eat dinner with him every night and tuck him into bed. When we finally could go on a vacation, we got to take him with. We got to watch him grow into a fine, loving, wonderful young man.
Mom is the one who missed out, BIG TIME.
Financially "punishing" the Dad for not taking the child for summer is not the way to go. He is already punishing himself by not spending time with the child when he can, only he doesn't know it yet. Child support is supposed to include extracurricular activities, the other half is supposed to be supplied by the custodial parent. If you can't afford the camp, enjoy the extra time you get to spend with your son. They grow up too fast.