In the early days of Internet retail, some consumers had their first online-shopping experiences during the holidays, leading them to keep returning to a particular site in later months.

WSJ: AHEAD OF THE TAPE: The Limits of Black Friday and Cyber Monday

Vodka shots, being charitable, and having sex seem to be pretty distinct experiences although I can easily imagine too many of the first and some of the second leading to the third more often than the participants would otherwise admit.

FORBES: Neurobiology Says Diversify Your Pleasures or Risk Addiction