They do not have the same kind of stake in making sure information ir reliable because their goal is to sell a product (which sometimes mean they have a stake in distorting information to make products seem better than they actually are in various ways). Newspapers, authors of books, historical societies, etc. are selling a product to but it is an information product with them standing behind it. A retail site selling a toy train provides product information details about the toy because people don't buy products without information on them, but they are selling the toy train, not the information. Moreover, information products are often written by people trained in providing information; researchers, librarians, journalists. So ask yourself: Who's writing the blurb accompanying the toy train and what procedures are in place to make sure it's accurate?