I'm unsure of how sophism fits into this. While there is a claim of rich people paying for the benefits of breastmilk, I don't see how that translates into charging for an education, or using deceptive and fallacious rhetorical methods to bring an audience to the side of the breastmilk buyers.
I'm just curious as to how you come to the conclusion that sophistry is employed. I don't mean to be offensive or degrading in any way. Be assured that I do understand, and mostly agree with the disgust you express about the inappropriateness of breastfeeding adults for money when it can be put to better use feeding infants.