I have been dealing with this question for the past week or so because someone kept emailing me asking for free samples and finally ranked me out because I would not send him a free sample of a $1.50 item to the UK. He pretty much said I was evil. I asked a number of other people near my niche what they did about free samples. They all said that any free samples are included in an actual purchase, and that otherwise, they charge for samples. One mentioned that she charges for samples but will take that charge off a subsequent purchase. I liked that idea and made it my policy.