Most physicians deny their professional integrity can be "bought" by something as trivial as a cup of coffee or a free lunch. In this paper, we review the social science literature arguing that "gifting" physicians in this way is, in fact, a highly successful method of boosting drug sales. Unlike ordinary consumer goods, the sale of prescription drugs does not take place directly between the producer and the consumer; rather, prescription drug sales are mediated by the physician who writes the script for the medication. Pharmaceutical sales practices are geared toward influencing physician drug recognition so that, when prescriptions are written, their drug is the first one that comes to mind. Even small gifts produce in their recipients a disproportionately powerful willingness to reciprocate in some manner. The simple act of providing food has been shown to make any message more palatable and more likely to be favorably received. We argue that physician prescribing habits should be based upon careful consideration of what medication is really in the patient's best clinical interests, not on who most recently provided the doctor with a free lunch.