I don't think there's any legitimate reason to be given the products.
I've never been given a product to try but I still manage to sell it, and I've sold everything from shoes, electrical appliances, toys, books, I even worked in a ship's chandler.
What the tat peddlers think about a product is of zero interest to me, they are not going to say this serum gave me a rash, or this polyester top made me sweat buckets are they, it's always I love this, all my girlfriends love this, the bin men love this!
All I want from the tat peddlers is information, sizes, measurments, ingredients, how much wattage an electrical item uses, etc instead of the lazy cop out 'all the details are on the website, go and have a look'.