From MAC Pro:
Most primary packaging of M·A·C products is accepted as Back to M·A·C "currency." M·A·C does not accept the following as a part of the program:
Secondary packaging of any sort [paper box, plastic/cellophane wrapper, shopping bags, etc.]
Samples [sample containers, special/trial size products for promotional/seasonal kits]
Cosmetic applicators/tools [disposables, puffs, sponges, scissors, spatulas, swabs, sharpeners, tweezers, curlers]
Accessories [bags, belts, makeup cases, lashes, Blot Film]
HTH!