In considering opening an affiliate site using Datafeedr with Wordpress, going with one main site and then adding stores under it certainly saves money in hosting, domain registration, Datafeedr store cost, etc. (Ex: the main site is uber.com and then the stores under it are uber.com/furniture and uber.com/cars, etc. and subsequently uber.com/cars/ford.) This is especially a money saver if you want to have, say, 10 stores under uber.com.
My question: What is the downside of using secondary sites under the main one? Is it that the search engines won't pick up the secondary sites as well? Perchance, is it a Datafeedr or Wordpress technical issue? Something else in theory?
The concept: promote the uber site and then expand the secondary sites to have their own domain if they start to do well. (Pointing the uber.com/whatever to the new site once it goes up.) Of course, going with separate sites for each product category from the start is possible, but that would be about quadruple the annual expense.