I've thought it odd, that the HBS I've been in and those online carry a number of brands of yeast, yet only stock one brand of nutrient.
The HBS closest for me, The Home Wine, Beer and Cheesemaking Shop. Only sells the owners blended nutrient of Superfood Plus with additional DAP and VITAMIX. This is what he uses at his winery, which leads me to believe what he sells is based on personal bias.
Anthony