Companies make samples of their products to show the buyers so the buyers will decide what they want, and buy said products. but they will all be one size, for example large t shirts, size 9 shoes, 27 ski boots.
Some times the reps will buy the samples from the companies, some times the reps just get given the samples.
Then they will usually have sample sales, usually lots of different companies at once. Usually the products are very cheap because the reps paid nothing/next to nothing for them. So if you happen to be a sample size, large shirts, size 9 shoes etc you are in luck.