When you are so drunk that you end up stealing a shopping cart from a store or from the street and you bring it home for no apparent reason. Usually people don't know what to do with it the next day but are too embarassed to return it.
"Hey dude, my sister was so shitfaced last night that she and her friends ended up drunkarting again. She woke up this morning with a shopping cart sitting there in her kitchen. Dude, this is so fucked up, she has real issues. She's been drunkarting too much lately"