It's being offered by Sam's Club, and the application form does have a place to enter your Sam's membership number. But you can just leave it blank and you'll still get your sample.
Samples will take four weeks to be delivered to your mailbox.
The new mother of seven, I'm also a journalist who is using those skills to search out the best cheap deals out there. All the while, I'll keep in mind what my Dad used to say: "It isn't a bargain if you don't need it."