Because the entire reformster universe runs on money (rather than conviction or proof or widespread grassroots support), it's useful to understand how buying support works.
It's perhaps most useful to understand how it doesn't work. Sometimes people get the impression that some shadowy figure delivers a bag of money to Representative Burgwarble or the Big Fat Ideas Thinky Tank and the recipient says, "Okay then. I'll be happy to now support whatever you tell me to."
This is inefficient, and not so effective because your supporter-for-hire is not so convincing. It's like deciding you need a tall blond spokesmodel, so you hire a short brunette and try to make her over. No-- it's much more efficient and effective to find a tall blonde who can talk.
So, for instance, when we are confronted with teachers speaking out in support of Common Core (like the four teacher spokespersons for Jeb Bush's Learn More Go Further program) I doubt that we're seeing turncoats who decided to embrace CCSS for some quick money. That spokesperson process starts by hunting down teachers who actually think Common Core is great (whether they actually understand what it truly is or not is a whole other issue that needn't be addressed). We can even formalize the search by having, say, a teacher of the year contest that includes loving the Core as a criterion. These are not people who are selling out; these are people who feel fortunate for being rewarded for what they already believe.
We can hire for other skills sets. For instance, some people love to argue. They love the battle, the chess game, the rhetorical constructs. You probably knew at least a couple of these people in college, people who could see the whole strategy and tactics of an argument laid out and just couldn't wait to fire it up and who would just light up when faced with a similarly-skilled opponent. This is that guy who stayed up till 3 AM arguing that Hitler could have been an effective world leader or that Communism is actually viable. These folks may have a particular ideological bent, but they can construct an argument for anything and sometimes consider it a special challenge to argue for something they actually believe is wrong. "Facts" are malleable and adaptable; the only true value is winning. Money is a good measure of score. People who lose their cool and get all emotional are deserving of little respect.
In politics, the Supremes have shown no understanding of how the purchase of politicians works these days. It's not "Here's a bag of money. Pass my bill." Politician's number one job is to get re-elected, and campaigns are incredibly expensive. That money has to come from somewhere. If you are an elected official, the people with the money are the people who decide whether you will keep your job or not. That means that these people are the people you must keep happy, the people you must convince you're doing well. The people with money are literally your bosses. And like any other boss, they will hire the people who they think will best fit their organization's goals.(They will also make it hard for headhunters to hire anyone away from them, because in every area other than teaching, they recognize that you have to outbid rival employers.)
When advocating for your cause, you yourself might be a cynical, opportunistic, money-grubbing, amoral, brazenly self-centered person. But that's not who you send out into the public sphere to make your case. For the voice and face of your cause, you need somebody who actually believes in the snake oil that you are selling.
The generals in these battles may well be reptilian wretches, but the front-line troops will be cute little earnest puppies.
So groups like StudentsFirst, Students Matter, Learn More Go Further, and Teach for America may be led with people of bad intent, but they have found earnest, sincere people to be the public faces of their initiatives.
The oldest trick in the book is to use the earnest puppies as a shield. Lots of people wanted to attack the Vergara suit; nobody wanted to be seen attacking nine fresh-faced teens. TFA deserves all the scorn and pushback that can be mounted, but nobody looks good trashing some earnest college grad who just wants to help poor kids.
It's useful to remember that not everybody who opposes us is knowingly wrong, in it for the money, sneaky and dishonest. Sometimes we aren't facing wolves in sheeps' clothing; we're facing actual sheep who disagree with us. We need to choose our tactics acordingly.