A shoobie tan occurs when a person normally wears socks and/or shoes that cover their feet, and they also wear shorts. This results in the quite unattractive tan in which their feet are completely white while their legs, from the ankle up, are tanned. People with shoobie tans are usually seen on the beach in flip flops, unaware of their less-than attractive appearance.
Friend: Yo Dan, put some shoes on bro!
Dan: Yeah I know, I'm only wearing flip flops to get rid of my hideous shoobie tan.