@ Stiffler--

Will I get in legal trouble if I buy contact lenses without a copy of my prescription?

-You won’t break any laws, but the company is selling you a prescription device as if it were an over-the-counter device. In legal terms, this misbrands the device. The company is also violating FTC regulations by selling you contact lenses without having your prescription. For more information, see the The Contact Lens Rule: A Guide for Prescribers and Sellers¹.

(Source: http://www.fda.gov/medicaldevices/productsandmedicalprocedures/homehealthandconsumer/consumerproducts/contactlenses/ucm062347.htm)