When a company is about to launch a cream or another skin care product, they will appreciate an unbiased opinion from potential customers. By delivering free samples they will get into the head of the customer and make sure that he is satisfied with the skin care product that will finally hit the shelves. There are certain surveys and questionnaires attached to the freebie, so they will get a feedback on various products offered and also learn more about each person's preferences.
While the free product samples will shed a little light about what the public expects from that particular item, the survey will help the company acquire more relevant data. These can be used in the long run, and the best thing is that the entire operation is a win-win situation. The manufacturer will produce better stuff, which addresses real needs, while the ones filling in the surveys will get their freebies right away.