Okay, so the East Compton Clovers refuse a sponsorship from Torrance's dad, but will accept it from the corporate sponsors of Pauletta Patton, even though they probably aren't much different from Torrance's dad's company.
One of the other squad members brings this up while they're writing the letter. Isis justifies it by saying that Pauletta is from their neighborhood, so it doesn't count.
Most likely it was because the help came from the enemy.
Also, it must feel pretty patronizing for the poor and (mostly) black Clovers to accept money from rich white folks. As Isis points out, they don't want charity, they want to make it to the finals through own effort. Writing Pauletta Patton is their own idea and their own effort, so getting the money through her is not the same as getting it from Torrance.
The Toros REALLY dodged a bullet by hiring Sparky, yet it seems that EVERYONE gets pissed at Torrance. If the team had stuck with the original, stolen, choreography, it would have been just them and the Clovers doing the same routine, setting off a whole investigation about WHY, and possibly ending in disqualification and even the NCA taking back some of the trophies. As it was, the school lucked out and became just another victim in a scam ring. Yet no one notices this
Not surprising; all the other cheerleaders on the squad were characterized as less than intelligent, so they probably didn't think this through.
Well, technically it was still her fault that they got suckered by a scam artist. I guess they were mad that Torrance didn't check the guy out more thoroughly before hiring him. If she had hired a legitimate choreographer the plan would have worked perfectly. They dodged a bullet to be sure, but I guess their thinking was that if Torrance had done better research the bullet would never have fired in the first place (if that makes any sense).