For me, it is not the bodybuilder that endorses the supplement site that makes me decide where I buy my supplements . Its about the type and quality of supplements and who offers them at a better and cost effective price.
Sure, I have favorite bodybuilders but I dont purchase supplements directly from their sites for the fact that I find other sites have the same supplements for a better price.
I price compare and usually either shop at 1fast400 or muscleshoppe for my supplements.
The owners of the supplements sites (Mike McCandles of 1fast400.com, Deluca of Bodybuilding.com, Labrada.. just to name a few) have their own opinions but their opinions does not dictate where I purchase my supplements from.
It all comes down to the price and quality and effectiveness of the supplements for me....not because a bodybuilder endorses it...