if you have to watch an infomercial, it's either a scam, a sales pitch, or at the least, a waste of time
usually an "online co-op" is a wholesale group buy - like, brand XYZ will sell us, a group of people not an authorized retailer, a case of widgets at wholesale cost but we have to get together and make one order, so everyone send me your money for wholesale cost plus a small markup for my trouble, I'll buy the case and ship the individual widgets to everyone, what a deal!