When you buy all sorts of junk food
stinking with bad fat, cholesterol
and all those things you crave but which your badass
doctor would advise against and put them at the bottom of the shopping
bag and then cover them with a handful of fruits and vagetables.
It can also be applied to any other situations in which you buy something you are not very proud of, put it at the bottom of the shopping bag and then cover it with other items you are very proud to show off
Derived from combining "shop" and "conceal"