Depending on what state they are in Wal-Mart might have gotten themselves sued for discrimination if they refused to give the AFA the same opportunity to sell their products for a comission as other organizations.
Walmart catering to NAMBLA?
NAMBLA supports illegal activity. The AFA supports immoral activity, however homosexuals are a legally protected minority in some states. The governments of those states have have basically made it illegal for Walmart to choose not to do business with homosexuals just because they are homosexual.
I Walmart doesn't want to do business with protected "minorities" the only real choice they would seem to have is to cease to do business in that state.
However, if they are really donating to the AFA, then they would seem to be showing support for that organization. However, I don't put much credibility into claims that Walmart donated to the organization unless Walmart confirms that they made the donation.
In pretty much all these protests against Walmart, the truth has been a rare commodity.
NAMBLA supports illegal activity.
It's illegal in the United States but that makes no difference. For what it's worth, NAMBLA was based out of Denmark the last I heard. If Walmart supported any organization, illegal or not, and that organization was one in which you are opposed, perhaps then you would better understand the position of the AFA.
And legally protected minorities or not, Walmart has past the point for what many consider acceptable, some of whom have decided to stop doing business with Walmart which is their personal decision based on Walmart's actions.