My two cents for what's it's worth is don't expect free samples. Courteous, professional conduct and great customer service is to me, the name of the game and builds repeat customers.
If an online retailer decides to send you a free sample be courteous in return and thank them. It's the icing on the cake.
Many years ago at Christmas time, the company I was working for, always gave a Christmas cash bonus to their employees. I remember how angry and disgruntled one particular employee was because he stated that his bonus should have been larger than he received. I told him to be thankful he got anything and to be thankful for his job with so many people unemployed.